Who ya gonna call? Sperm busters

Tom walks into the room wearing a peculiar key chain.

Dad: Tom, what's on your belt?
Tom: Oh, it's a key chain that Zac gave me. It's a ghost that glows in the dark.
Dad: It doesn't look like a ghost to me. It looks like a giant sperm!
Tom: No, its a ghost. What's a sperm anyway?
Dad: Male reproductive cells. And it's definitely a sperm.
Tom: Mom, Zac gave me this, it's a ghost isn't it?
Mom: Well.... I did get it for Zac from a reproductive health booth at work. So it's not a ghost.
Dad: Bwahahaha haha.
Tom: *Rips it off his belt* I can't believe Zac gave this to me.
Eva: I'll have it.