Antisocial, dorky boy seeks fun-loving, sexy vampire for blood-sucking and transforming into her minion. 
One sleepless night, Ko slips out to walk the streets. Life after dark is a revelation! Especially when he meets flirtatious Nazuna. Except that she's a vampire. That's okay. He wants to become a creature of the night too. But transformation doesn't come that easily... 
While Ko does his best to repair his friendship with Mahiru, Mahiru comes to a momentous decision regarding his romantic relationship with vampire Kiku. But first he opens his heart to Nazuna about his troubled family. And then Ko and Kyoko confront Kiku...