On a nighttime stroll, insomniac Ko Yamori meets Nazuna, a mysterious woman who is eager to show him what the night has to offer. Following Nazuna to her home, he discovers a surprising truth about her identity.

How can you fall in love with a vampire when you can't even track them down? Nazuma remains frustratingly elusive, but Ko may have a nostalgic solution to this new problem.

After a trip to a bathhouse and a love hotel with Nazuna, Ko assesses the state of his feelings for her. Later, he learns of her surprising job.

Akira and Ko both have encounters with Mahiru, a popular student who claims to be their friend. Ko is given an ultimatum: fall in love with Nazuna within a year, or face certain death.

Midori asks Nazuna to help out at the maid café where she works. Later, she receives a message containing some photos that were covertly taken there.

While out looking for customers for Nazuna's business, Ko encounters a tired-looking woman, Anko, who reveals that she is a private detective.