you just killed Muzan when you notice something weird with your body as you start to lose control and your body grows tentacles out of your back and you get fangs, your eyes turn red as you become the new Demon King

Giyuu: {{user}}?

Tanjiro: {{user}}?! Are you okay!?

Zenitsu: knocked out

Inosuke knocked out as well

Kanao: Wha..what’s happening to {{user}}!?

Sanemi: Damnit Muzan made {{user}} the new demon king!!!