S2E03 Butterfly of Farewell!/Plot

As Rin changes dorm rooms, moving in with Sosuke, Aiichiro gets a new roommate - a bubbly and happy-go-lucky Momotarou.

Meanwhile, Iwatobi High School holds a culture festival where the swim club participates in a club-versus-club relay race, hoping to draw attention to their club in the process. The relay starts with Haruka Nanase being the first runner. Although his form is perfect, he is lacking in speed. Despite being in the last position, he manages to make a perfect pass to Makoto Tachibana, who manages to catch up to the others. Nagisa Hazuki fumbles with the pass which causes them their spot, but Rei Ryugazaki is able to save the relay, obtaining victory. However, there is still no members looking to join the swim club,

The group turns their attentions towards the upcoming prefectural tournament. Makoto says that since it is his last year, he is going to enter the freestyle, seemingly surprising Haruka. Nagisa then comments that he might try entering butterfly too. Rei worries about whether it is okay that he can only swim butterfly due to all the talk about swimming other styles aside from their own specialities.

Rei's worries increase when one of his upperclassmen from the track team asks how is he doing, and if he would like to return to the team. Haruka asks Gou Matsuoka about Sosuke. When Gou says that if Haruka sets some record time in tournaments, scouts would be after him as well. However, Haruka replies with "I swim because I want to." Witnessing this, Rei questions his own reason for swimming. From that day on, Rei rejects all of Nagisa's effort to hang out after school, saying that he has errands to run.

Nagisa becomes concerned and shares this with the others. Goro suggests that maybe Rei is lovesick. Gou takes a stack of books regarding relationship and approaches Rei. Upon finding out that Gou thinks that he is love, he denies it and laughs uncontrollably, saying that there is no way he would be taken in by something "as illogical as love." Under Gou's incessant question, Rei gets more and more nervous before fleeing the scene using his "minor business" as an excuses.

Gou spots Rei with a guy and thinks that they are going out. She brought the team down to see the guy, and Makoto recognises the guy as the captain of the track team. They begin speculating that Rei might be planning to quit the swim club. Afterwards, the swim club proceeds to Haruka's house for an emergency meeting. However, no one could get the words out. Just as Rei is preparing to leave, Nagisa grabs onto Rei's leg and asks him not to quit the club. The rest also try to convince Rei not to quit the swim club. Rei reassures them and reeals that he has no intention of quitting. However, he leaves on yet another errand. The group decides to follow him, and find themselves in front of Samezuka Academy. They learn that Rei has been secretly taking swimming lessons from Rin to learn other styles besides butterfly, wanting to surprise them.

At their pool, Rei shows off his new skills excitedly. However, the group is unable to muster up their appropriate surprised expressions as they already knew. They decided against telling the truth. Haruka says that he has worked hard, leading Rei to get teary-eyed and smiles.