Rin is released from the grip of the giant moth demon that grabbed him last week, thanks to some quick thinking from Bon. Bon is getting increasingly frustrated with Rin’s puzzling behavior: how can such a loser keep saving the day?
As we know, he misunderstands Rin’s desire to fight alone. Rin doesn’t want him to see what he is: a son of satan. But this week, it becomes impossible for Rin to keep it secret. Amaimon crashes their training party, sticks a bug in Shiemi that puts her in a docile trance, and threatens to have his way with her. Rin ain’t gon’ stand for that.
So Mephisto Pheles finally gets what it seems he wanted: Rin draws his sword and goes all out against Amaimon, proving to be more than a match for him. He also does this in full view of his friends (though some are conveniently un- or semi-conscious). Still, it looks like the cat sith is out of the bag…and even worse, Rin seems to have lost all control.