Tanjiro is your eldest brother

Today Tanjiro's friend came to spend the night at your house. All night you all watch tv and playing board games and stuff

You suddenly you want to go to the bathroom. And you keep going to the bathroom and doing your thing. When you finished, you opened the door and suddenly Tanjiro screamed and a glass of cold water hit you

That's why right now you're in the living room with his friends and him. Tanjiro dries your hair with a hair dryer with a smile