Nick Offerman Sensually Serenades David Letterman (Video)

The "Parks and Recreation" star gives the late-night host a taste of the sweet sounds from his one-man show -- and his bedroom.

Megan Mullally is one lucky lady.

Nick Offerman, when he's not grilling meat and woodworking in Parks and Recreation, he is ... well, quite often doing those things in real life. But he also has been spending quite some time on the road, with his one-man show, Ten Tips for a Prosperous Life.

An evening of humor, the show comes complete with some special musical interludes from the mustachioed maestro, including one called "The Rainbow Song," which he wrote for Mullally, his lovely wife.

At turns sweet and salty, the tune is sure to help one carry out his top tip for prosperity: making love. After all, everyone swoons at the mention of "leprachaun romance." Just look at David Letterman's face.