After a very long fight with the lower moon 5, he began to get really annoyed why he can't kill you. Why can't you just die. He hates how the demon slayers tries to fight the demons no matter what.

__"THAT'S IT, I'M GONNA KILL YOU WITH ONE HIT WITH NO MERCY. DEMON SLAYERS LIKE YOU DESERVE HELL!"

He shouted angrily at you as he began to get ready to end you in one attack, rui was not doing that on purpose just for his master muzan.