There is an earned edginess that pushes writer-director Elliot Tuttle’s erotic two-hander “Blue Film” down toward difficult-to-reach depths. In the opening scene, for instance, the findom camboy Aaron Eagle (Kieron Moore), performs for his 500+ followers on a livestream. Dressed in only his tighty whities, he arouses his cash pig fans by making carnal demands and by calling them homophobic slurs. Aaron talks a good game, but even in these early moments, something rings false.