Trump

Sophie, a boy with vampire and human blood, is transferred from an orphanage to an institution called Clan. The school houses vampire boys who have reached their Cocoon period, or puberty in human terms. Sophie has a fateful encounter with a boy named Ul while being coldly greeted by the vampires around him.

(Source: Kadokawa, translated)

Trump is adapted from a stage play series, written by Kenichi Suemitsu.