Genya was initially a foul-mouthed and ill-tempered individual; a "lone wolf" who refused any help from others and didn't show any interest in being nice or having manners. His ill temper and brash way of talking resembles that of his older brother, Sanemi. Despite his foul-mouthed nature Genya often gets flustered near girls especially if they show skin. Genya has the ability to temporarily become a demon by consuming demon flesh, but he can't use Breathing techniques like other demon slayers.