Ten Narita

A boy at the same school as Karin. After he mistakenly confesses to Karin in place of her older sister, he halfheartedly agrees to an alliance with her; Ten is to provide information about his older brother, whom Karin has a crush on, while Karin provides relationship advice regarding her older sister, whom Ten has a crush on.

~!After Karin reveals to Ten that, in reality, she likes him and not his brother, he affirms his love for Karin's sister but acknowledges Karin's own challenge to him: to see which of them can enter a relationship with their loved one first.!~