code. 3 is the name of the third chapter of the Given manga.
Haruki and Kaji discuss Ritsuka and how good he is at the guitar. Ritsuka is teaching Mafuyu the guitar chords but exasperated he is unsure if Mafuyu is really getting it. Joining them, Haruki, Ritsuka, and Kaji together bring up student's jobs for Mafuyu to consider if he is serious about music.
Ritsuka's basketball friend notices that he has been hanging around a lot with his bandmates recently, specifically with Mafuyu. His friends both want to know how they got friendly especially when neither are sociable. A female friend describes Mafuyu as hard to approach but observes that he has suddenly gotten attached to Ritsuka. Sure enough, someone calls out that Mafuyu himself is there for Ritsuka.
Continuing to teach him the guitar, Ritsuka notes Mafuyu learns fast but wonders why he started doing music. Thinking how he got his guitar, Mafuyu denies it was handed down by his father, stating that he does not have one.
Then asking if Mafuyu has any music he likes, Ritsuka hears him sing one from memory. He is struck by Mafuyu's singing with it sending shivers down his spine and with his heart beating Ritsuka asks him to join their band.