Fuck both so fucking hot! Dude on bottom knows how it's done- tight leg muscles and feet flex! Those hot toes with the rest of his body! Yum! Lick that those and the cum!
IF the guy on top wasn't stroking furiously enough to shake the bed or grind mattress springs, the guy on the lower bunk wearing headphones MIGHT have been unaware. The guy on top certainly knew from the creaking & breathing what was happening beneath him & his buddy's orgasm appears to trigger his own. When one started stroking, the other probably got turned on.
It appears they did cum at the same time. Whether they both realized the other did too is questionable because the guy in the lower bunk was wearing headphones. He didn't hear the top bunk dude trying to alert him that he was coming down from the top bunk. Poor lower bunk dude hit his back while getting out from the lower bunk.