Freaky snail situation

[Dash]

I noticed little bumps on the shells of my two big turbo snails but figured they were just some sort of filter creature. Then, I thought these bumps were moving, but dismissed it as my bad eyesight. So I was peering into my tank at a random hour in the middle of the night as I like to do, and got a good look. Turns out the bumps do move, and they are babies of varying sizes that are just smooching off their parents. Pretty freaky looking as there are multiple mouths, antennae, whatevers all moving around in a squishy way. The biggest "baby" also lifted it's shell and I saw what looks like a bunch of eggs? What the hay? Can't find much info on this online.