Rock/Mega Man and Roll are helping Dr Right/Light clean his house (Rock is vacuuming and Roll is dusting), when Roll (who happens to be behind Rock right then and there) trips over the cord of Rock’s vacuum cleaner, and as she falls, she instinctively reaches for the closest thing she can find, which just so happens to be the back of Rock’s shorts. So, as you might have guessed, Rock’s shorts are pulled down, revealing his tighty-whities (what, you thought those blue trunks that were part of his combat suit were his underwear?). Dr Light, upon seeing this, remarks, "And that's why almost no one uses a corded vacuum cleaner any more."
References for Rock, Roll, and Dr Light below (as well as pose/scene reference--source is the George Brown, Class Clown series of children's books).
