In episode one, Ren alights from the limousine and when is offered an umbrella as it was snowing, he refuses it and approaches the guards along with Otoya to let Haruka take the entrance exam for Saotome Academy. He tells the guards that the reason why Haruka was late was, she was helping a lost girl find her mother. In a flashback from earlier on, Ren is seen in his limousine watching Haruka reunite the girl with her mother. He even hands Haruka a new umbrella as she had given her's to the little girl. Ren tells the guards that kind-hearted, caring and helpful students like Haruka should be allowed to enroll in the academy. When Otoya says that he and Ren are in this, Ren brushes this off saying that he and Haruka have been tied together by fate much to Otoya's dismay. One of the guards recieves a phone call and then informs Haruka that she can take the entrance exam which delights both Ren and Otoya.
Ren is later seen in the lunch queue calling Syo 'Ochibi' (Munchkin) and says, 'I had my eye on the little lamb first.' Haruka recognises him and hastily thanks him again for helping her on the day of the entrance exam. When he tells her that it was fate meeting her again, Masato appears and tells him that there are limits to his jokes. Ren mocks Masato for being placed in A-class, since he is in S-class (a special class). Tomochika runs up to Haruka exclaiming, 'Lifesaver B was Jinguji Ren?!?' She reveals to Haruka that Ren is the heir for the 'Jinguji Financial Group' while Masato is the heir to the 'Hijirikawa Financial Group'. Ren is then sitting at a table with Syo and waving at a group of girls, making them excited.
In episode two, he is seen in his room with Masato when Otoya goes up to him to ask how he writes his lyrics. He tells Otoya that he lives to love beautiful woman and from that, his songs become love songs. And as he throws his dart onto his dart board, he says that his love always hits his prey which Otoya doesn't get at all.
In episode three, Ren is seen in the courtyard entertaining his fan girls with his saxophone. When his song is over, his fangirls praise his performance. He spots Masato looking concerned and persumbly gets a bit jealous as Masato was concerned for Haruka. He is then seen at the end of the episode watching Haruka and Masato from afar, extremely jealous seeing how close the two are. 'So that's how it is... Hijirikawa.' he says.
In episode four, Ren is seen walking down the hallway next to the courtyard being followed by his fangirls. He is holding a rose in his hand telling his fangirls that he is planning on giving it to someone unless they can sweep him off his feet. Otoya comments on how Ren could get away with a line like that and Natsuki compliments Ren on how the goddess of love is so fond of him. When Ren sees Masato telling Haruka where to start the music and extremely close to her, he gets jealous and approaches Masato saying 'When did you become so cosy with the little lamb... Hijirikawa.' He tells Masato that he and Haruka have been tied together by fate ever since he first met her. Ren goes over to Haruka and pulls her up onto her feet, hands her the rose and tells her that he'd rather not let her stray far. As he forces the rose into her hand, he says 'I've been looking for someone to feel the sea breeze with.' to which Haruka exclaims 'N-Now?!' He winks at her and when he says of course, he amusingly watches Haruka panic, but gets offended when Masato tells Haruka that he was only teasing her and that she can't believe whatever he says. In the middle of shooting Masato down, he is interrupted by his classmate, Syo, who comes running up to him to remind him of his lyrics assignment which he still hasn't turned in yet and the harsh punishment Hyuga-sensei had promised him, but Ren brushes this aside.
Hyuga-sensei appears and Ren shows no sign of fright and casually greets his teacher with 'Hi, Ryuga-san.' Hyuga-sensei tells Ren that he always skips classes and never turns in any homework, and he warns him that if he continues to show his frivolous atitude, he will show no mercy and threatens to expel him on the spot, which Ren doesn't seem to care about, but terrifies the others. Ren, maintaining his composure, smirks, goes up to Hyuga-sensei and whispers into his ear, 'A scowl is never popular with the ladies.' As he walks away, Hyuga-sensei tells him that he is serious and if Ren's lyrics assignment is not handed in by the end of tomorrow, he will definitely be out of the academy. Ren, seemingly to have heard the threat, waves his hand as he rejoins his fangirls. After Tomochika learns from Otoya about Ren being threatened to be expelled, she comments saying that it's his own fault for being a slacker and Otoya reveals that Ren and Masato are old friends and have known each other through their parents.
He is then shown in his room playing darts. Masato asks him whether he is going to ignore Hyuga-sensei's warning which Ren brushes it off and tells Masato to mind his own business. In Masato's flashback of their childhood, they first met at a social party when Ren was six years old. Ren saw Masato leaning against the wall and saw that he wasn't enjoying the party. He went over to Masato and asked 'Boring, isn't it?' and when Masato didn't answer, he asked again, 'It's boring, right?' Masato looked at him. He grinned and asked 'Wanna skip out of here?' which Masato thought sounded fun and agreed. They ended up sneaking out of the party and played by a nearby lake. Ren and Masato grew up, realised their positions as heirs to their family Financial groups and stopped talking to each other. Ren reminices of how he ended up in Saotome Academy. It is revealed that his older brother, made him enroll at the academy to get into the show business, and serve as the billboard for his family. Ren then asks Masato if he is really worried about him, but Masato doesn't answer which Ren angrily brushes off.
Ren is later seen on the roof of the school scribbling down some lyrics for his assignment. He runs out of ideas, tears out the paper from it's notepad and crumples it up saying that it is ridiculous. He shoves the crumpled piece of paper into his pockets, takes out his saxophone and begins to play a song, which is heard by Haruka and Masato. Haruka shows up on the roof, having had followed the sound of his saxophone and upon seeing her, Ren tells her that she looks like a flower, glittering in the setting sun. Haruka compliments his song saying that it was so beautiful that it drew her here, which makes Ren happy. He approaches Haruka saying 'I don't care what the reason is... As long as it brings the two of us together.' Ren pulls his hands out of his pocket, accidentally causing the crumpled paper to fall out, as he places his hands on Haruka's shoulders. Haruka spots the crumpled paper, bends down and picks it up. She is about to read it when Ren snatches it out of her hands. She asks if it is his lyrics assignment when she sees some writing and appears relieved and happy much to Ren's surprise. Haruka tells Ren that she does not want to think of what will happen to him if he didn't turn his lyrics in on time and asks if he had already finished them. Ren brushes this off by telling her that it is time he should leave the academy and that he's tired of being here.
They are interrupted by Masato, who had also been drawn by Ren's song on the saxophone. Ren tells Masato that he didn't go to Saotome Academy because he wanted to, he was dumped there and that he has no reason to be here. Masato angrily tells him that it's a lie and says that the song he heard Ren playing on the saxophone was not a lie and why didn't he show it. At that moment, Ren rips up his lyrics and allows the pieces to drift in the wind saying that he is not going to waste anymore time being in the academy 'gambling everything on worthless lyrics' which causes him to recieve a punch across the face from Masato. As Masato leaves, Ren smirks and calls him a 'Hothead', but is surprised when Haruka tells him that she will search for his lyrics. Ren skips class the next day and is seen in the fields resting against a tree whistling a tune. He begins reminicing his childhood at age eight and of when his father caught him watching DVD's of his mother's performance saying that he thought he had discarded them after she passed away. Ren asks his father if he hated his mother, but his father refused to answer that question and left the room. Ren had a tape behind his back and hurriedly ran to the park to listen to it, and there he found out that the tape was from his mother who composed a tune while she was pregnant with him. She had dedicated the tune to him, telling him to be a healthy and considerate child. As he listens to the tape he starts crying and the flashback ends.
Haruka shows up and reads out his lyrics and tells him that it is great, which surprises him. She tells him that falling in love with someone and that if he unleashes his feelings, everything will shine, and start to move, full of life. She presents him with the lyrics she had managed to find with two pieces missing and tells him that one of her grandmother's favourite expressions is: Always have a caring heart. Haruka pleads to Ren not to quit and to express how he really feels. Ren at that point, smiles and tells Haruka that she is very kind and how she skipped class to search for his lyrics, but then is surprised when she presses the lyrics into his hand informs him that she will look for the remaining pieces and runs off. After she leaves, Ren tells her in his mind, 'No matter where you look, you won't find it. I haven't written it yet.' Time runs out and Hyuga-sensei proceeds to look for Ren to expel him.
Ren is then seen in the speaker room where he turns on the school speakers and announces to everyone that he has finished his lyrics assignment and will unleash his feelings that he has supressed. The lights turn on in the speaker room and Ren shouts, 'It's showtime!' He plays his saxophone and sings his lyrics, 'Sekai no Hate Made Believe Heart' (To the ends of the Earth, Believe Heart) with his friends joining him in the speaker room and dancing to his song. Ren is not expelled in the end.
In episode five, Ren is seen in the study hall being surrounded by his fangirls from afar while the guys from A-class, Haruka and Tomochika discuss Syo's acrophobia, since he is going to audition to star alongside his idol, Hyuga-sensei, who is well known for his role in a drama called the 'Prince of Fights', and that it is full of high places. When Otoya offers to help Syo overcome his fear of heights, Ren approaches Syo, surprising him, and asks if he could join in the training, saying that it is interesting and a good way to kill time. He is seen throughout Syo's training cheering on him with the others. Ren also watches Saotome hypnotise Syo to find out what caused his acrophobia.
He is then seen with the others when they find out that Syo changed his mind about auditioning for he had discovered that the role was going to be the main character's younger sister. Ren is then seen walking away with Masato when Syo breaks down after his idol mistook him for a girl, having had been tackled into a dress by Natsuki earlier.
In episode six, when everyone is expressing their concerns for Haruka going to HAYATO's concert by herself, Ren appears behind her and offers to take her there and suggests that they call it a date, but when Masato says 'Now I'm even more worried.' Ren gets offended. He is then seen in his room reading a magazine when Otoya bursts in telling him and Masato that they're not going to believe this. Otoya turns on the TV on Ren's side of the room to show them a live footage of Natsuki as Satsuki performing 'Orion de SHOUT OUT' (SHOUT OUT at Orion). Assuming that Satsuki is still Natsuki, Ren smirks and says 'This is interesting...' After Syo switches Satsuki back into Natsuki, he is shown still staring at the screen with Masato and Otoya as they watch Syo angrily yell at Natsuki with confusion.
In episode seven, Ren is in the recording studio with Syo and the rest of S-class watching Tokiya's performance. He appears shocked when Hyuga-sensei kicks Tokiya out of S-class for having no 'heart' whenever he sings. He doesn't appear in the rest of the episode.
In episode eight, Ren is first shown in the classroom being told by Hyuga, along with his classmates, that the school will be taking the students to an island over the break, and he listens with a serious look on his face as they are encouraged to use the time to consider who they want as a partner.
Once at the island, he is show surrounded by his fan girls. All of them are asking who he will choose as a partner. He makes them go wild with a smooth answer, but then turns serious as he thinks about it. He is later shown taking a shower. Once he gets out, Masato asks him who he intends to choose. Ren says that he's going with his heart, but would be much happier if he could pursue her along with it. When Masato says that he's chosen in his head and intends to tell her soon enough, Ren's eyes widen and he looks at him with suspicion.
He is shown at the end of the episode, waiting on the dock for Haruka. When he sees her, he tells her goodmorning, before proceeding to say that he wants her as his partner, winking at her.
He is first seen waiting at the top of the stairs for Haruka with a huge bouque of roses. He tells her that he's been looking for her, before forcing the bouque into her hands. He then whispers that he'd turned in his preferred partner form with her name on it. When she appears shocked and troubled by this, he asks her if she is "still a little lost sheep." He caresses the side of her face, while whispering that she doesn't need to doubt because he can make her happy. When she backs away, he continues to advance and says that he will sing a passionate song for her. When she hits the wall, he places his hand beside her head. He then turns serious and thanks her for awakening his passion for music, and tells her that he needs her. He says that he wants to look for what is beyond the awakening, together with her. He leans in as if to kiss her, but backs off saying that he'll be waiting for a positive answer.
As he leaves, he notices Masato, who had been eavesdropping on the entire conversation. He mockingly says that spying is a nice hobby. Masato angrily says that Haruka is not like any of the other girls, and demands that Ren stay away from her. When Ren asks what he'll do if he won't, Masato tells him that he'll never forgive that. Ren gets annoyed, but starts laughing, asking if this is their rivalry rearing its head. Which Masato angrily denied before saying that he needs Haruka, and that any other partner is just unthinkable. Ren glares at him, momentarily taken aback, before saying that he's the one who really needs her, shocking Masato. Ren declares that he is the one. Masato says that he won't let him have her before walking away.
He is later seen in his room throwing darts, but missing the bullseye, which is strange for him. He says that their are a total of five applicants for Haruka, and muses that she has a big decision to make. When Masato says that the number doesn't matter, only the performance, Ren says that it is unusual for them to agree.
He is later shown at night, on the roof where he was playing his saxophone before, twirling a dart between his fingers. He looks up at the sky with conflicted eyes, clearly worried about who Haruka will choose.
In episode twelve, after learning that Tokiya is actually HAYATO, Ren is seen in the practice room with the other guys (minus Tokiya), Haruka and Tomochika, clearly fustrated and angry. While the other guys vent out their anger at Tokiya, Ren remains silent througout the whole conversation. He is then seen on the roof when Masato confronts him and asks why he didn't say anything. Ren replies saying that he's sick of imagining what Tokiya did during his free time. When Masato asked whether if it would be better to exclude Tokiya from their group debut and go on as a fivesome, Ren brushes it off saying that it is unusual for Masato to say those words. Masato compliments Ren that he has changed, for Ren used to be rebellious, frivolous and would do something without thinking twice.
When Tokiya finally makes it back to the academy, he is angrily confronted by the guys who demand answers from him, Ren doing most of the talking. 'So you finally show up, but it was just to whine to the little lamb?' Ren asks Tokiya. When Haruka tries to defend Tokiya, having had bumped into him when he returned, Ren cuts her off by telling her to zip it as he wanted Tokiya to answer for himself. Tokiya sincerely apologises to everyone for decieving them and pleads to let him debut with them for their graduation audition. 'Together? Can we trust you?' says Ren unconvinced of Tokiya's apology, 'You say this to us now, after all this time...' He tells Tokiya that "each of us thinks we can sing the lady's (Haruka) songs best" and were his words all a lie? Tokiya tells Ren that he has changed, and Haruka's idea of making them sing as group had given him hope, and how she always wished for them to sing together, Ren still looks unconvinced. He manages to convince Ren saying that he has finally found a place where he can sing and after telling Haruka that he loves her songs and that he wants to continue singing the songs she writes, she accepts and hearing this, Ren smiles and asks, 'So, are we finally at the starting line?' showing that he has forgiven Tokiya.
Saotome then announces the group's debut and names them ST☆RISH. Ren along with the guys appear surprised that they have already passed the graduation audition after Saotome listened to their song, 'Maji Love 1000%'. As ST☆RISH celebrate their debut, Ren says 'Plus Nanami.' then places his hands on Haruka's shoulders and winks at her, with Tokiya telling her that they will be debuting as seven as she is their songwriter. When Saotome tells ST☆RISH that Haruka cannot be their composer, Ren, along with the other members get shocked and angry.
In episode thirteen, he is seen outside with ST☆RISH, Haruka and Tomochika, venting his anger and fustration that Saotome won't let Haruka debut as their songwriter. 'If we're not doing the Lady's songs,' says Ren, 'I'm out.' which Otoya and Syo agree to. Haruka quickly brushes it off and tells them to make their debut as it is their only chance and to not worry about her, only making him more concerned. On the day of their rehearsal, Ren along with ST☆RISH purposely miss practice as they are still angry at Saotome for excluding Haruka from the project. 'I expect he'll storm in here any minute, gaffawing as always...' says Ren and after saying that, the door bursts open and instead of Saotome like he was expecting, it's Tomochika instead. She informs ST☆RISH that Haruka has ran away, which shocks him and the other members.
Ren is later seen with ST☆RISH outside Haruka's grandmother's house singing 'Mirai Chizu' (Map of the Future) to convince Haruka to return to the academy. Ren tells Haruka that she is not just a fan, but a great composer. After each of the members tell her that they need her and that they don't want any other songwriter but her, touched, Haruka tearfully declares that she is done running away, and will be their one and only songwriter and that they will only sing the songs she composes. As she happily weeps, Ren and Natsuki are bending over her and along with the other members, comfort her. Saotome as usual, appears out of the blue and reveals to Haruka and ST☆RISH that the whole thing was just an act. He never intended to cut Haruka from the program, but had to test her first to see whether she was worthy enough to be their composer. After Saotome announces that Haruka from now on will write their songs, ST☆RISH happily celebrates.
He is later seen with ST☆RISH doing a group hug and hi-fiving Haruka as they proceed to go on stage to make their debut.
In episode one, Ren surprises Haruka by presenting her with a garden of roses in front of her dorm room. He greets her holding a bouquet of roses and compliments that she is looking beautiful and cute as ever, making her blush. He tells her that he is looking forward to their life together in the Master Course and that he named the roses 'Lady Haruka'. Before leaving, he gives Haruka a peck on the cheek and telling her that she is cute again. He is later seen in the main hall with Otoya and Masato. When he comments saying that they're living under the same roof as Haruka, Masato gets serious and Ren laughs it off saying 'Oh, you're so serious. Don't be so mad'. He gets suspicious when he sees Otoya happily daydreaming. With a smirk he asks Otoya, 'What were you just thinking about?' causing Otoya to panic and accidentally reveal how happy he is to be close to Haruka as the rest of ST☆RISH appear.
Haruka shows up and reveals to the boys that over the holidays, she had written them each an individual song. Ren praises her and comments saying that he couldn't ask for a better present. They are interrupted by the arrival of Saotome who welcomes them to the Master Course. He introduces ST☆RISH to their mentors, QUARTET KNIGHT who perform their song, 'POISON KISS'. As they watch QUARTET KNIGHT's performance, Ren comments with a smirk, 'Not bad'. Ren and Masato are assigned to Kurosaki Ranmaru. When Ranmaru voices out not being interested in being ST☆RISH's mentors, after Masato tells him that they are not approaching this half-heartedly, Ren confidentally says 'We're prepared. Besides, I think we can beat that song of yours.' He appears shocked upon learning that their mentors have to share a room with them.
In episode two, Ren is with ST☆RISH wandering around the grounds after dance practice. Masato tells Ren that his dancing was lazy which Ren brushes aside. He and ST☆RISH hear Cecil singing 'Ai no Reincarnation' (Reincarnation of Love) and spots Haruka following Cecil's voice. He is startled by Cecil's appearance and gets jealous and shocked along with ST☆RISH when Cecil kisses Haruka's hand. When Cecil tries to kiss Haruka, Ren and ST☆RISH in a fit of jealousy charge towards them and pulls Cecil off Haruka with Otoya, Syo and Natsuki.