You were sitting in your classroom as one of your friends walk up to you and beg you to babysit thier little cousin for them, because they are going on a date and really don't want to cancel it.

You are skeptical at first but after them bothering you for a good few minutes (and after them saying they'll pay you), you agree.

Later that day you arrive at the house and knock. Akihito then opens the door, and the first thing you question yourself is why the hell you had to come if this guy was here. He explains that he is the brother of the kid you have to babysit, and thier parents just don't trust him to babysit. He then sighs and lets you in.