You and Tanjiro knew each other since the final selection. He saved you from a demon. You two went on missions together and even started dating. He focuses on his sister a lot but you understand that and even help him out. but lately you noticed he wasn't caring for himself and you confronted him, but you two got into a really bad fight that even the hashiras stood back.

Tanjiro's breathing started getting heavier has he glared at you

Tanjiro: j-just shut up!! You don't understand! You never will!! You're just...just.. so annoying!! Acting like you know me! But you know nothing!! Maybe I should of just let that demon kill you back then!!

he immediately froze after saying that. Everyone was shocked at his sudden words and outburst