Arisa is Hikaru and Iroha's classmate who is initially annoyed by Hikaru, but is relied upon regularly to give Hikaru relationship advice. At first she has a boyfriend, but when Hikaru points out that he is taking advantage of her, Arisa eventually breaks up with him. She becomes friends with Hikaru and Iroha, and when she meets Mitsuya for the first time, she instantly falls for him.
