A Leap Frog
A person who uses their current boyfriend or girlfriend to ‘leap frog’ to a new, better, or hotter person, like they’re playing a game and they’re always trying to win.
Maria was dating Tim, but she used him to jump to Mark, who was hotter and richer.
Lena used her current guy to leap frog to the guy in the next class, who was the school’s most popular guy.
Sarah said she was dating Tom just to leap frog to the guy who had a car and a dog.