Introductions discussion

I stumbled upon this place while looking for an answer to something I saw happen. My partner was wearing a cage, and when I got home early, I caught him watching porn and jerking off inside it just as he does without one. The fit is good, but he feels discomfort if his erection swells against the bars. His testicles get squeezed too. How can he enjoy himself at all while trying so hard to work out an orgasm? Is it even possible for him to jerk off and cum?