2girls, armchair, aru (blue archive), bangs, black serafuku, black thighhighs, blue archive, blunt bangs, chair, cross, cross earrings, demon horns, demon wings, earrings, ghost costume, halloween, halo, horns, ikky, jack-o'-lantern, jewelry, long hair, multiple girls, mutsuki (blue archive), neckerchief, picture frame, pink hair, pleated skirt, red neckerchief, school uniform, serafuku, sitting, skeleton, skirt, thigh strap, thighhighs, wings, yellow eyes