Noblesse

When Cadis Etrama Di Raizel or Rai, as he is known, awakens after 820 years, he discovers a modern world he simply doesn't understand. Once an extremely powerful member of the Nobles, a race of nearly immortal and powerful creatures, Rai decides to start again as a high school student at Ye Ran High School, founded by his former servant Frankenstein, who is somehow still alive after all these centuries. Frankenstein’s goal—to help his powerful, vampire-like master learn about human life and culture as he protects him from the modern forces Rai cannot fathom.

Rai's somewhat peaceful new life is about to be disturbed by The Union, a secret organization interested in using his powers to further their own malicious goals.

When past clashes with present in this innovative take on familiar dark fantasy tropes, Rai must do everything in his power to ensure the Union doesn’t control his destiny, and that he can continue to integrate himself into this new, confusing modern world...

(Source: WEBTOON Unscrolled)