Courtship

Courtship is a state where a person already has a girlfriend, but still tentative. That is, the relationship has not lead to a higher stage. Most perpetrators were teens who want to taste the sweetness of love in the era.

Well sometimes courtship could also mean. The guy and the girl is both single. Then the guy sends advances to the girl to show his interest and it's up to the girl to accept it or not. If the girl accepts the guy then that's the time they are called boyfriend and girlfriend.