There are some unwritten friend rules that guys have to live by.
One of the lesser known ones is the beer goggle cockblock.
If you see your buddy wrapped up in the tentacles of a monster, PULL HIM AWAY.
He will get upset. He will want to fight you. He will tell you to fuck off. Pull him away anyway. He will thank you tomorrow.
Now, this sounds like an easy thing to do, but it can be tough. You just push through that mental bullshit that will hit you like "He's a big boy, he can handle it." or "Damn, that is SO FUNNY." It's NOT funny. When your buddies are messing around with monsters, it devalues YOU. Maybe not at this party, but the next one.
People remember that your "group" has that guy in it that nailed that monster. If you think girls don't know who's fucking who, and who is friends them, then you're kidding yourself. Don't lose the friend, save him.
Here are some helpful examples: