I was thinking of the Daedric quest for Sanguine which has nothing to do with the Brotherhood. Sanguine sends you to a party and wants you to use a spell without telling you what to do.
Tap for spoiler
The spell removes the clothes of everyone in the room including you and you have to flee the place naked to get your gear back.
Ah ok. Because of the dress rules in the title, I thought it was about that one countess’s party you have to crash.
Hey, why not use the Stark Reality spell on the party goers from this quest, too? It is a fun spell, after all.
I think it’s the same quest
I was thinking of the Daedric quest for Sanguine which has nothing to do with the Brotherhood. Sanguine sends you to a party and wants you to use a spell without telling you what to do.
Tap for spoiler
The spell removes the clothes of everyone in the room including you and you have to flee the place naked to get your gear back.