If you're a woman, you might think you know all there is to know about the female reproductive system, but you also might realize that you don't know all that much — beyond the general basics — about the male reproductive system. Sure, you learned the general makeup of the male and female reproductive systems years ago in science or health classes and you feel pretty confident that you know how they work, but there are also some weird and fascinating things about the male reproductive system you never knew, or, at least, that most people probably don't know all that much about.
The human body is an amazing thing, but if there are things about your own body that you're not entirely clear on (and there almost certainly are), you can pretty much bet that there are also things about other bodies that are a little bit of a mystery to you. Some of the weirder facts about the male reproductive system in particular and the human body in general might just be things that you'd never even considered possible or true before. Others really are so fascinating that they serve as a reminder that the human body is even more complex than you might've thought — and that there's so much more you have to learn about it.