One of our favorite things about San Diego Comic Con, going on now, is all the cosplay in effect. There's still a few more days of the convention, but John Barrowman has already snatched the crown for best costumes at the annual pop-culture confab.

He might also get the award for most costume changes.

Here's Barrowman as Marvel's Squirrel Girl.

Chauvinist space captain Zapp Brannigan from Futurama.

It can be hard for celebs to peruse SDCC without being molested by throngs of fans, so many wear disguises. Here's John as a cross-dressing Kylo Ren from

He ended his Friday as Harley Quinn (classic version).

Of course, he wear his civvies for some of the con, like when he got a kiss from geek heartthrob Chris Hardwick.

And this sci-fi manwich with Nathan Fillion, Alan Tudyk and Casper Van Dien.

And licked balls with Stephen Amell.

The two Arrow stars also donned high heels for a panel (allegedly for charity).

Do you have a Barrowman sighting at SDCC? Share with the group in the comment section!