Necromentia

Necromentia is a 2009 horror film directed by Pearry Teo.

Travis cares for his mentally disabled younger brother and works as a torturer for hire. He is also addicted to heroin it is ketamine, however, that catapults him into the realm of a blackeyed demon called Morbius. Morbius informs Travis that his brother has been taken by another demonic troublemaker called Mister Skinny. Mister Skinny appears as a diaperwearing fat caucasian butcher in a pig mask who first entices the boy to eviscerate his slumbering babysitter. If Travis helps Morbius exact vengeance then Morbius will allegedly help Travis find his dead brother.Morbius instructs Travis to find Hagen and extract an agreement to use him as a gateway to Hell. Travis does this by assuring the desperate Hagen that the process will allow Hagen to enter the next realm and possibly retrieve the soul of his decomposing lover. Travis proceeds to carve demonic symbols into Hagens back and sends him straight into Hell, where he is gruesomely mutilated by a monstrous eyeless beast before ever setting out in search of his lover. Travis follows in search of his own brother and is disabled and dragged into the darkness by the hideous beast. ........

Source: Wikipedia