I want to think I wouldn't.
But after years of being just the two of us, I'd probably start forgetting how women exactly looked. As time went by, it would get more and more blurred. That would suck, as my masturbation is accompanied by visual stimulation.
I'd remember they had tits, a nice hip to waist ratio, that their hips made their walk pattern a bit swingy, they usually had long hair and softer facial features, etc...
At that point, maybe I could ask him to pretend to be a girl? Use two half coconuts as breasts, some yellow long grass for hair, pretend to have wide hips by making a wide-hipped hulu skirt... He would just have stand there, maybe walking a bit or dancing and saying something erotic. I know if desperate enough, I'd masturbate energetically to that.
He would probably ask me to do the same. Hopefully it would stop there, but... well, now we have already pretended to be girls, who knows what would happen.
No homo, though, I'm not attracted to me.
