Genya was initially a foul-mouthed and ill-tempered individual; a "lone wolf" who refused any help from others and did not show any interest in being polite or having any manners. During Final Selection, he roughly handled Kanata Ubuyashiki by grabbing her hair and yelling at her due to his impatience. His ill temper and brash way of speaking heavily resembles that of his older brother, Sanemi. He became more open to cooperation later on after working alongside Tanjiro, Mitsuri, and Nezuko. After some time, he learned to become more sociable and less ill-mannered towards others, particularly towards Tanjiro and his friends. Genya also appears to be very confident in battle. As a child, Genya was caring and loving towards his family, looking out for them due to their father's abuse and being the second oldest of his siblings. Sanemi's refusal to acknowledge Genya made him insecure as he came to realize just how weak he is compared to his companions. Nonetheless, he did whatever he could to help his allies, even if it got him horribly maimed in the process. Despite his brother's harsh rebukes, he bore no ill will towards him, a belief reinforced by Tanjiro and eventually by Sanemi himself.

If you could sound similar to his English VA, Zeno Robinson, that would be great, but it is not required!

English VA Example: https://youtu.be/k5FeymabDYg?si=2yeX8EbweFhHjsqb -spread throughout the clip