PandoraHearts

Oz Vessalius, heir to a prestigious noble family, is on the brink of his coming-of-age ceremony when he's suddenly cast into the Abyss, a nightmarish realm of eternal darkness, for a crime he doesn't understand. There, he encounters Alice, a mysterious girl known as a "Chain," who offers him a contract to escape: in exchange for her freedom, Oz must help her uncover her lost memories and the truth behind his banishment. As they return to the real world, Oz and Alice navigate a web of political intrigue, supernatural forces, and shadowy organizations, joined by allies like the enigmatic Gilbert and the fierce Sharon. (Unreviewed summary by Grok 2)