Question: would you date a guy 3 years younger?
Answer: According to xkcd, the standard creepiness rule is you shouldn't date someone younger than your age, divided by two, plus seven. So if you are twenty, 20/2 is 10, and 10+7 is 17 so the youngest person you would date is 17. ... It's no more wrong than a female dating a guy 2 to 3 years older. Or 6 years older or younger.