Darker than Black: Kuro no Keiyakusha Gaiden

After escaping Hell's Gate, Hei and Yin go on the run together, posing as a married couple while hiding at a quiet inn. Hei hopes the distance will give them time to recover, but a fellow Contractor among the guests has been sent to kill him, making their refuge dangerous almost immediately.

The attacks that follow are only the beginning. Yin's abilities and emotions are changing in ways Hei cannot understand, attracting the attention of powerful organizations and placing their bond under increasing pressure. As the pair flee from country to country, what happens between them fills the missing path toward the darker, more isolated Hei who will later return to Japan.