Enmu

Enmu (魘夢) is a demon in Demon Slayer: Kimetsu no Yaiba (Kimetsu no Yaiba). He serves as the main antagonist of the Mugen Train Arc.

He is a member of the Twelve Kizuki (the elite demons directly serving Muzan Kibutsuji), holding the position of Lower Rank One (Lower Moon One).

Enmu is known for his sadistic and psychotic personality—he takes twisted pleasure in human suffering, particularly through psychological torment and manipulating victims' minds. His Blood Demon Art allows him to induce sleep and control dreams, trapping people in illusions (often merging dream and reality) to torment or kill them indirectly.

Physically, he appears as a slender, pale young man in his mid-20s with a neat, formal look (black suit-like attire, distinctive hair that gradients from black to red-pink/blue tones, and unique eye markings including the kanji for "Lower One").