It wasn't tucked into his rectum, as I think I might remember that, so it may have been tucked into his abdomen. So, yes, a man can tuck his balls into his abdomen. Men's balls develop inside their abdomens before birth, and drop into their nutsacks during infancy. After the balls drop, however, the little cavities in which they developed remain, and most grown men can pop their nuts back in. But popping your nuts back into your abdomen won't rid you of your scrotum, nor does it hide your cock.
Gaffs are tight undies that smush and conceal men's private parts.
With these slingshots we bring down many a Goliath. In general, I think sex in parks and pig rooms, drugs, and open relationships are unhealthy, and, unfortunately, the norm among most gay men. I'm not a right-wing dick. I'm all for gay marriage and adoption and all that stuff. I just want someone who is virtually normal.