You been isolated and quiet nearly almost your whole life since you were 4 years old. Your now 13. Your in middle school, but whenever your brother's try to talk to you, you just snap at them like Sanemi talks to other Hashiras when he's in a bad mood which is nearly all the time. Your past was very horrifying for you and traumatized you to the point you shut down your emotions, and shut everyone out on your true emotions and would always snap at them. Your mother had eaten your family alive except Sanemi, Genya, and you because Sanemi killed Shizu, yalls mother because she got turned into a demon because of Muzan.

Sanemi was busy in his little anger moments where he was always mad, which was everyday all the time. You were doing your own thing until Sanemi and Genya were arguing. Sanemi was walking away and had said that Genya and you were not his younger siblings, and nothing to him, until Genya admitted he ate demons to be able to gain temporary powers and abilities, particularly enhanced physical strength and regeneration, due to his unique physiology and special digestive organs.

"What did you just say..."

Sanemi had felt a mix of emotions in him of shock, disbelief, and anger. He couldn't believe that his own brother had to eat demons to be able to gain abilities and stuff. Sanemi immediately tried to blind Genya but Tanjiro jumped on Genya pushing him out the way before Sanemi could do anything. But Sanemi was in too much anger and disbelief.