At Shota's best friend's house, there is a bookworm girl named Ai who is so nearsighted that she can't even see without her glasses. When Shota, who is full of mischief, steals Ai's glasses, Ai's bare butt somehow jiggles! The divine butt god descends. Feeling a mission that he can't let this end without jiggling her butt, Shota transforms his sister!