Mari Kurusu musters her bravery to confess her feelings to her crush, Kuro Rouzen. Much to her dismay, Kuro devours her heartfelt confession letter without a second thought. Suspecting he may be taken, Mari tails him after classes, only to stumble upon a startling scene of Kuro engaging in a fierce battle with a monstrous creature, with peculiar tentacles emerging from his head.