Soldier fails the 'stiffie' test.

Not young enough to have been fresh-faced squaddies straight out of school, these guys are probably territorial army volunteer reservists. Nevertheless, they well know that they have to do what they're ordered to do without question, failure to do so being 'rewarded' with a dishonourable discharge from the service they are so keen to have trained for. 
So when they're lined up and told to strip off their tops and drop their pants they do it. And when they're ordered to get themselves hard, if they think abut it at all they just assume it's part of a general medical inspection, and they carry out what's commanded. But among the line-up there's one of them whose cock remains stubbornly asleep despite being tugged and manipulated by the commanding officer. They are getting a bit nervous as they think that they'll next be ordered to suck on the soft cock in turn, and to keep sucking until it's fully erect. Their biggest fear is that they'll be seen as getting pleasure from the act of sucking, betrayed by their own cock not de-tumescing or getting even stiffer than it already is, attracting all the scorn it will get. It would be too much to bear if they were seen to be enjoying sucking cock even if their looks say otherwise. Unlike their words, a cock cannot lie. 
And btw, isn't that guy second from left wearing a ring around his cock and balls? Is this their first day back and he's forgotten to remove it? Same goes for those two with neck-chains.