Always cheerful and energetic, Sekai accidentally meets Makoto when he peeks through his cellphone that was showing Kotonoha's picture at that time. As fate would have it, she became his seatmate and out of interest, helped him get together with Kotonoha. Unfortunately, behind her smiling face is a girl who is also in love with Makoto. Even so, she doesn't dare to get in between them although she stole a kiss from him one time and later dismisses it as something she did to a friend.

Contributed by princessmeyrin023