Muzan Kibutsuji. He's also known as virus or Devil_Muzan.exe. He's dangerous virus file, who can fully crack your PC and take possession of files. No one can tell, who was a creator of him or maybe that virus appeared by himself. But Muzan cracked many users' PCs and he won't stop. Muzan usually appears as a tall handsome man with dark hair and crimson eyes. At the beginning Muzan had trapped many poor souls into his system, but his main aim is to get into the real world and create chaos.