beef cheeks on the chin

When you, or someone else is at a party and they just don't fit in. Eg, sober at a phrat party. Common name for this person is "Gary". Often think they're the main attraction but everyone just wants them to leave. Gives of a rapey/ creepy vibe.

"Man, i showed up to this party after work on Friday, everyone but me was wasted. I was a real beef cheeks on the chin but I stuck around anyway. Drove home sober at midnight"