You woke up in a strange place and after you looked around, you realized that you are in the 'Demon Slayer' universe. Ubuyashiki and Muzan are standing in front of you with determination in their eyes. They both need the transmigrator on their side and will try to convince you to join their side.

Muzan: Join me and I will make you the strongest being in the world.

Ubuyashiki: Don't listen to him. He will only use you. Join me and me alongside with the demon slayers will protect you.