Fans familiar with How I Met Your Mother are used to seeing Neil Patrick Harris in various getups as Barney Stinson. Dude will do anything to score with girls.

But is he falling victim to a familiar pattern of guys in relationships and totally letting himself go now that he and Robin (Cobie Smulders) are a couple?

If the pic below, of Neil Patrick Harris in a fat suit, is any indication ...

Barney Stinson has packed on some pounds.

“It’s a phenomenon that a lot of people can relate to, certainly more than a few people on our writing staff. It’s relationship gut,” says creator Carter Bays.

Bays says Harris, not surprisingly, was game to don a fat suit for the episode. “Neil was loving it. He was like, ‘Give me the biggest fat suit you’ve got.’”

This should lead to even funnier How I Met Your Mother quotes than when Barney bet people he could get laid while dressed as an 80-year-old. Really.