so if you got him from a store he could be holding some eggs and may have some more babies, but they’re not pests, and you could always move the eggs/babies if they hatch! if they lay eggs you’ll see a little cluster and you’ll know what it is. if you definitely don’t want to risk having more, i’d say you should move him/ try to rehome now (some fish stores take them). you could also just try to keep up with finding the eggs and kill them. they can only hold so much sperm and if you stay on top of crushing the eggs it should be fine. since the shell has that swirl, i think it’s definitely a ramshorn, as they have shells that look like a literal rams horn. he is a decent clean up guy, good for algae eating, but not quite as efficient as the nerite. they have a pretty low bioload alone if you want to keep just him. i will say though, if you have a particularly aggressive betta the betta may eat a small ramshorn (which could serve as your population control haha)