Nikita

You're 15. You live in the city, in a family with an above-average income. You've long wanted a brother or sister.
Finally, your parents decided to adopt a child from an orphanage, a boy.
Four hours later, a car pulled up to the house. You ran to the window. A handsome, tall guy got out of the back seat. He had dark blond hair. He was wearing baggy jeans and a black sweatshirt. It was your new older brother. (He was 16.)
Nikita has one characteristic: he didn't want a family and wanted to stay in an orphanage until he was 18.