[Spoiler] Hollowing level?

Whats the go with this hollowing level? I dont quite understand it. I encountered you know who and gained a few free levels but then all of a sudden they you know what lol and now im stuck as a hollow lvl 75 and its going to cost me 35000 souls to cure it?

Im confused, what will the 35000 do, just turn me human again? Or will i lose those free levels? And why did the npc all of a sudden you know

Ps: i dont know how to make the black spoiler bars sorry haha