Aubrey Plaza, Jim O'Heir make out while 'Parks and Rec' co-stars sing 'Bye, Bye Li'l Sebastian'

NEW YORK, Feb. 25 (UPI) -- The cast of Parks and Recreation appeared on Late Night with Seth Meyers and sang the now-wrapped sitcom's anthem "Bye, Bye Li'l Sebastian."

Co-stars Jim O'Heir and Aubrey Plaza stole the show by passionately kissing in the background as Chris Pratt earnestly strummed a guitar and led the rest of the cast members in singing the farewell song to a beloved miniature horse that died in the third season of the show. Co-stars Amy Poehler, Aziz Ansari, Nick Offerman and Retta -- who were holding up lighters -- dissolved into laughter as they saw what O'Heir and Plaza were doing.

"I can't look at it! I can't watch it!" Retta gasped between giggles. "Oh, my God!"

The series about municipal bureacrats in a small town in Indiana wrapped its seven-season run Tuesday.