He reappropriated it himself, 'Stoney' did no such thing so far. It can become nonnegative for him, but so far his (lack of a) name is not a topic yet other than being used by others (than these two girls) to dehumanise him.
A reappropriated nickname is called '
geuzennaam' in Dutch, I always find it odd English doesn't have a specific word for this concept beyond
reappropriation.