So, it's safe to say there's something going on between Katy Perry and John Mayer, right??
If you think they're just friends, you've got another thing coming!
Even though her former rumored BF Diplo was in attendance at the Met Gala on Monday evening, Katy Kat clearly chose to spend her night with on-again off-again and on-again man friend John!
[ Related: Katy, Madonna, & Lady GaGa Hug It Out ]
While the duo arrived one after the other to The Standard Hotel for the after-party last night, they were inseparable once inside.
According to some sneaky spies at the event, Katy and Johnny Boy were very much together — they spent the majority of their evening side-by-side, as well as chatting with other celebs together.
The twosome were also spotted locking lips and holding hands inside the Boom Boom Room at the hotel!!
This relationship is SO on again.
Although we probably could've told you that after they were caught on camera hanging out at her house during the Super Bowl!
Cheers to the happy couple!
[Image via Ginsburg Spaly.]