黒の魔王 (Series) favorite_border

[DeepL Translation - needs review] Introduction to Volume 1: Mao Kurono, an ordinary high school boy, suddenly falls into a coma due to a headache. The next thing he knows, he wakes up in an experimental facility in another world. After being subjected to unreasonably repeated torture, a ray of light shines through, but is it hope or a new kind of despair?

(Translator: DeepL)