The drains are used to drain away excess fluid, which should result in less swelling.
They are just pulled out afterwards, just before you go home. It shouldn’t really hurt coming out, it should just be a pull (they aren’t attached to anything, just placed), but on few occasions they can get stuck as the incisions are too tight to release them. They really aren’t as bad as you think.
I didn’t have them, so obviously I’m only speaking from what iv learnt xx