Looking for a OLD south park episode

i barely remember it but i cant find anyone that remembers it, i also have concept art.

https://snipboard.io/tfnW73.jpg

so when i was a young chap. i watched southpark randomly at like 1 am.

anyway this episode had some blue gown lady in a mansion that was clearly abandoned and she came out from upstairs onto this overlook down to this main room, any way im pretty sure stan was at the bottom of the stairs, and cartmen made fun of the blue gowned women, she had barely any hair crazy looking and her face was her ass and her ass was her face, NOT to be confused with the ass faced couple. but yeah im pretty sure she pooped out of her face. and was talking out her ass. i dont know if this episode actually exists but its a core memory to me for south park so i have to debunk it. if anyone knows let me know