Yakumo has messy, medium-length black hair and purple eyes. He has two tattoos on his body; a small, black swallow between his collarbones, and a large, detailed owl on his back, with its wings covering the sides of his arms. He appears to have 'fangs' in the form of pronounced canine teeth.
Yakumo is an extroverted person who comes off as arrogant and loud. He frequently feigns having his feelings hurt when others annoy him, regardless whether it was intentional or not.