Yami Kakusei Shite Shujinkou ni Boko Sareru Kamaseinu ni Hyoui Shita ga Gensaku to Chigaisugite Tomadotteru

The villainous noble, Zenon Restinatra, is a disappointing "underdog" who gets beaten up by the protagonist in the original anime. "I," a mere fan of the original work, have possessed such a Zenon!? This place is completely the world of the anime, and when I tried out magic for starters, it was super fun. I've decided... I'm going to change Zenon's disappointing ending! The "do-over" life of a magic maniac begins!!

(Source: Kodansha, translated)