they definitely don’t have gag reflexes but I also think they could definitely pretend they have one just for the benefit of the one using them.
I need Zen to be on his knees and very patiently let the others inspect his pretty mouth; their fingers rubbing along his velvety silicone tongue; against the rubbery roof of his mouth where it’s nice and textured for added sensation and comfort; let them smear the silky-oily lube that is his fake saliva across the smooth bump of his lower lip… metal nice and warm, the curve made with a human’s comfort in mind so they have a good rest for their cock…
he’s a luxury model and he’s not shy about it.