[Minstrel's Rhapsody] Sigma

Sigma is a demon summoned by Angelica for her purposes of eradicating immortals. His given name was quite lame, and thus Angelica decided to change it into Sigma. He feeds off people to regenerate and strengthen himself. Despite being a demon, Sigma has a soft spot for little kids, and thus befriends Aimee quickly. He also has another form.