The stage of Kuroshitsuji II opens on the life of Alois Trancy, the young heir to the Trancy earldom. Though he is privileged now, such was not always the case for the hot-tempered boy. Kidnapped and forced into slavery at a young age, he was eventually rescued and returned home, only to have his beloved father pass away soon after.

However, there are certain individuals who doubt Alois' story and legitimacy. And rightfully so, because things in the Trancy household are not as they appear, starting with Alois' black-clad butler with supernatural abilities, Claude Faustus. Who exactly is the mysterious Claude, and what connection does he have with Alois?

Amid the web of lies and deceit running rampant in the mansion, the bond between Alois and Claude will be tested as hell itself arrives at their doorstep.