[Western Crossover] After Cosplaying as Muzan, I Became a Rare Healer Among Superheroes

Superman is the love interest. The protagonist cosplays as Muzan and transmigrates to a superhero world. They gain Muzan's abilities but also inherit some of his personality: being a coward. They fight enemies while sniffling and saying they're scared, then hide in Superman's broad chest. A dark yet kind version of Muzan as the protagonist, paired with the Man of Steel.

Detailed blurb to come.

Theme: Life means striving without end