After running late from school, Mio ends up being chased by a girl wearing a bear mask, which turns out to be her older sister playing a prank on her. Meanwhile, Nano is shocked to find the Professor has modified her body to produce desserts. Later, Mio lends Yüko her notebook, only to remember that she ended up drawing an erotic sketch of Köjirö in there, and attempts to get it back. Meanwhile, Misato tries to get Köjirö to cooperate with her on the festival committee seriously.