06/27/2012 20:23

By Marc Malkin

Justin Bieber and Selena Gomez were getting their party on last night.

The two were spotted late into the evening with Robert Pattinson and Katy Perry at Bootsy Bellows, a new club in West Hollywood.

"They were all hanging out in the VIP room," a source said. "They were all just talking and having a good time."

Don't worry, all was OK with Bieber, 18, and Gomez, 19, being in the 21-and-over club. The adults-only policy doesn't go into effect until the venue officially opens on Friday.

Also there were Perry's bestie, Raising Hope actress Shannon Woodward, former lovebirds Emma Roberts and Chord Overstreet, and Pretty Little Liars' Ashley Benson as well as club co-owners David Arquette and John Terzian.