A parasitic louse that crawls into your mouth, vampirizes your tongue, then clamps itself onto the withered stub so it can ride around inside you and drink your mucus for the rest of your mutual lives? Why, yes. It’s called symbiosis and it’s beautiful.
What? Relax. It’s going to be fine. This isn’t going to hurt. You won’t even miss your tongue—once the louse is latched onto the muscle, you can simply use its body as a tongue instead. These are exactly the kind of details that evolution has worked out for you, because evolution loves you and it wants you to be all right.