A "flame grill" also known as a "Flame Grillin" is the act of tackling some one to the floor, pulling down your pants, rubbing your anus cheeks against they're face and finally letting out a juicy fart. May require more than one person to perform.
Ryan:"Hey Christian lets give tyler a flame grill!"
Christian:"Yeah baby flame grillin love!"
Tyler: Eeeew! All I can taste is anus!
Ryan:Flame Grill Baby!