Yofukashi no Uta Season 2

Kou Yamori has made his decision: he wants to become a vampire, which means falling in love with Nazuna Nanakusa before the time available to him runs out. Yet after so many nights together, both discover that understanding “love” is far harder than simply spending time side by side, especially as the relationships between their human and vampire friends become more complicated as well.

Detective Anko Uguisu is closing in on the vampire community with the intention of killing them. Her investigation reveals that a vampire's fatal weakness is tied to something cherished during their human life, while Nazuna remembers almost nothing about hers. Protecting her now requires Kou to search through years Nazuna herself cannot recall. Their nightly romance becomes an investigation into a hidden past that may finally explain who Nazuna was before she became the person he knows.