When someone invades your personal space or privacy with the effect of causing harm or distraction. A person may beef the grill of another without necessarily intending to.
"Yo, why the fuck you all up in my face, beefing my grill and shit?"
"Man, Mitch just wouldn't leave me alone about that cigarette I 'owe' him. He was totally beefing my grill."
"Tyrone was beefing my grill hard, so I clocked his ugly face in."
When a male and female are engaged in the sexual act of 69ing, and the male is getting his testicles and/or ass licked while simultaneously thrusting his erection between his partner's breasts.