This is merely an exercise, not a sexual act in any way, it does not have any homosexual connotation at all. This is simply an ingenious way of doing calf raises. The calf raiser, or bull, will bend over with his armpits resting on a weight bar without weights on a flat bench. Then the spotter, or rider, will mount the calf raiser and straddle him directly above the buttocks. He will then lock his legs around the other mans lower torso. Then he places his hands on his hips and prepares to ride, in a completely heterosexual way. The Calf raiser will then begin to do calf raises with his partner as the weight. The partner will need to move his hips in a rythmic fasion in order to maintain balance while riding. He may opt to place both hands behind his head to change the muscle groups worked while he tries to maintain his balance. This is thought to be much more effective than the numerous machines made for this specific exercise that can have the weight adjusted with ease. It is a great workout and a great way to meet other completely heterosexual males with similar interests.
Guy #1: Hey I watched you drip dry in the shower today, you're gluts are awesome.
Guy #2: Yeah, thanks!
Guy #1: But you're calves could use a workout, maybe I could help you with that, how 'bout some Brokeback Bucca calf raises tomorrow?
Guy #2: You're on...right on.