The content is the same as above, but the hero knows Taekwondo (or Judo, I can't remember) and the whole school is afraid of him. Then the heroine looks like him after being disfigured in a car accident. The heroine recognizes him as her long-lost sister, and then they live together. Next is the funny story of two people at school!

I don't know if it is the one you are looking for! ! ! !