So I have big thighs and a thigh burn as a result so when the skin right there got loose I assumed it was due to the rubbing of my thighs. But then a few nights ago I popped it and hardened pus came out (a little bit) but now it’s like the thing has gotten bigger and actually feels a bit hard unlike at first when it just felt like loose skin. What is this?

UPDATE: these are more recent (right now) pictures