We went to a party that turned into a gang bang. Really felt similarly to you.
We didn’t know the hosts well. Far too many single men showed up. The house looked like it was between owners/tenants with minimal furnishings. The guys were mostly over machismo, treated the women, at best smugly, at worst with contempt like fuckwhore-toys.
We looked in on the action a couple of times thinking it would be hot but girls were handled too roughly, spanked, fucked really hard and aggressively with guys lined up, cheering shouting, calling names.
It really disgusted us. We had hoped to sneak into a quiet corner and entertain ourselves but when we saw this, we thanked the host and left.
If your gut is telling you that something isn’t right, listen to it.