You don't bring in a gay character as a way of commenting on gay issues. You have one there because he's real, and that's his life, no less so than your life is yours.
Teju ColeAt the emergence of the modern novel with Rabelais and Cervantes, all kinds of things were possible in a long-form prose work. Within a couple of hundred years, most of those possibilities were abandoned in favor of a text that efficiently transmitted sentiments.
Teju Cole