I don't really remember the summary but I do remember that it was about a boy and a girl who go to high school. The boy is really handsome and he acts narcissistic, and he is like the prince of the school. The girl always takes care of him and I think she liked him. One day another girl came to school and she looks exactly like the prince and there is this moment where they are just staring at each other. The girl gets jealous and stops taking care of the boy but the boy can't take care of himself and one day he comes to school in pajamas. Anyone know what I am talking about?

Right now I'm thinking Nishiki-kun no Nasugamama but... there's no "One day another girl came to school and she looks exactly like the prince and there is this moment where they are just staring at each other."

I'm getting an odd sense of deja-vu. I think there was a post like this before... O-O Tokimeki Gakuen Ouji Kumi ?