Justin Bieber: She Was Just 17 ... You Know What I Mean

Justin Bieber has made it clearer than ever -- Selena ain't his type no more -- because he hit the town in London Friday night with a Sofia Richie lookalike.

The Biebs and the chick hit up Tape nightclub. Here's what we don't know -- who she is, and what he's done with Sofia. He and Sofia boarded a private jet a few days ago but she was MIA Friday night.