Call of the Night, Vol. 15 By Kotoyama

Antisocial, dorky boy seeks fun-loving, sexy vampire for blood-sucking and transforming into her minion

To sign up for his class trip to Hokkaido, Ko has to, well, go to school! His estranged friend Mahiru decides to travel to the island as well, along with an unwelcome companion (unwelcome to Ko and company, that is). And things only get worse when Ko’s fanged female followers join him and Akira on the train ride there!