Is this Katy Perry's new guy?

It looks like Katy and the banjo-plucking musician, sometimes known as “Country” Winston Marshall, hooked up after a post show party.

Marshall was in Berlin for a series of intimate shows with his folk-rock band Mumford and Sons.

Katy Perry was playing the O2 Arena the same night. Our source says she and the band ended up hanging out for a night of post-performance partying, and Perry and Marshall got it on!