Darker Than Black Gaiden OVA
Fleeing from the outcome of his decision in the Hell’s Gate, superpowered Contractor Hei and his companion Yin take refuge in a quiet inn, adopting the guise of a married couple so as to not draw suspicion. In an effort to recoup from current events, Hei befriends the inn’s other guests. He finds that one of these is a fellow Contractor tasked with killing him. Their consequent encounter spells tragedy for both Hei and Yin, that are forced to struggle for their lives and grapple with all the psychological wounds sustained in their past life together.