art by Jack Kamen, story by Al Feldstein
Weird Science #8 (1951)
This story has space pilot Harry returning from a year in space to find that his nerdy roommate Walter has a gorgeous new fiancee, Diane. Apparently Harry has always stolen away any girl Walter was interested in, and Walter took advantage of Harry's year-long absence to get engaged. Harry proves to be a jackass by deciding to win Diane away from Walter, just for fun.
Diane appears to be an easy conquest for him, but then he finds himself unexpectedly falling in love with her. He breaks the news to Walter, who laughs hysterically at the idea. Harry decides to run off and marry Diane right away, only to find out... well, the title and the expectation of a surprise ending in a sci-fi story make the reveal a bit obvious. Not one of the best EC stories, the Kamen cheesecake is about the only redeeming features.