Dark Hunter is the second entry of Shibusawa Kou's "English Dream" series, following the three-part 'Emit'.

Jigen Academy is a secluded school, where the students with psychological scars come to heal and find their purpose in life. Mariko experiences a chain of vivid hallucinations after her father's remarriage and her new mother sends her away to attend Jigen Academy. There she meets two transfer students: a stoic young man Ran, whose being is consumed by a need for revenge, and a foreign woman with reckless driving skills. Mariko's encounter with them sets her on a path to unearth the mysteries within the Academy.

[Edited from Koei Wikia]