It was a pretty simple program, as he was lacking in coding knowledge: After a while of not breathing, his body would force a breath. No discomfort, no pain from having water in him... It was hardly better than pretending he needed air. Eventually, it occurred to him to try simulations instead. Most that he found and downloaded didn't have a breath meter of any sort, and most of what did wasn't good enough; either immediate "death" once he inhaled, or an ache as his "health" drained.
But, there was one. Made by a certain "Oculus Vulpis", it lauded itself on having realistic drowning in a variety of environments... If it worked, it'd be perfect! Loading it up as he recharged on a bench, the synth found himself on a beach, where he promptly swam into the water and dove under. The breath meter that came up was quite different from what he'd seen before, a container of sorts that had a gradually shrinking bubble. Putting that aside, he dove deep, all the way to the bottom, before blowing out most of his air in a cloud of bubbles. Then, preparing to be disappointed yet again, he intentionally took a breath-
And was caught off-guard as his throat seized for a moment. The bubble in his breath meter immediately popped, the synth gagging for a moment before coughing, followed by a forced gasp. Just like it'd said, this seemed a lot more realistic... And it felt surprisingly good! It was worth the effort in finding!
Some time after discovering the simulation, the synth managed to figure out how to make changes to it - turning off the NSFW filter, and making drowning go on longer. As he'd breathe water for a couple minutes, he'd jack off through the trunks the simulation always gave him, or even just let his arousal build on its own just from choking, the latter sometimes leading to a powerful hands-free orgasm. It never really got old, the feeling of his lungs rejecting the water they'd always been indifferent toward in reality.
Synths made by
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