Bloodletter said: T-those two shouldn't be able to mate!
I lol'd a little that you took the time to go look up the egg groups for this (unless you already had them memorized, which is amusing in and of itself.) I had to check, too.
Maybe it's just a guy with a drifloon mask...? Or, perhaps more accurately, maybe they can get away with it because there's no mating involved with anal.
Anyone with moderate experience with breeding Pogeymons since GSC era would have those egg groups pounded into their head by now. Ghosts are typically indeterminate, while Cloyster should be some kind of Water X group, which Drifloon doesn't fit the bill for.