Happy Days S02 E22 Kiss Me Sickly

"Those were the days of the 1950's...filled with innocence and the promise of even better days to come."

Fonzie asks Richie to watch after his girl, Denise, while he's out of town at a demolition derby. Denise, upon hearing what Fonzie's asked Richie to do, decides to test Richie's trustworthiness. Richie succumbs to temptation and makes out with Denise at Inspiriation Point, but he later finds out that she has mononucleosis.