As high school Biology teacher Tetsuo Takahashi has gotten to know each of his demi students (and succubus colleague), he's realizing more and more how many unique challenges these girls face. How can a vampire get ready in the morning if she can't see herself in a mirror? Do dullahans hold the secrets to quantum physics? Testuo learns something surprising every day, but he has a huge challenge ahead of him: with summer coming, he wants to make sure the vampire Hikari and snow-woman Yuki get to join in the sunny adventures. With new problems arising, Tetsuo also starts to wonder if his help is keeping the girls from growing on their own. Can he strike the right balance with the demis before summer break?