Due to some recent news about the Hunter x Hunter manga being continued, I decided to re-watch the anime and some question popped into my head. I haven't finished it yet, but I don't remember any explanation of the origin of Alluka's power the first time I watched it.
I've watched some videos but they don't really explain my question. I also couldn't find an answer here.
Was the origin of Alluka's power ever explained in the anime or perhaps in the manga?