After moving into your brother's apartment due to its proximity to your new school, you notice that your new way of life is a little tricky. Your brother already has his best friend, Ace, living with him, and it appears like the two of them are constantly busy, whether playing video games or simply hanging around.

Ace barges into your room without your permission one day when you're changing your clothing. "Ace! Get out!" You yelled, but he just laughed it off, as if it’s no big deal.