Soldiers (take your pick of factions) take a fort/camp/whatever. One of the prisoners is a hot young lad (of legal age). A group of soldiers prepare to rape him, expecting a fight, but to their amazement being gangfucked rough and hard by big hairy muscly dudes is the kid's dream come true.

Rough hard sexing ensues as the youth satisfies his horny captors. I'm not going to say this is a prompt for "consensual" pr0n because, well, it's not as though he has a choice in that situation. But the kid is well up for it, that's the main thing.