So, let's give it a shot cause I don't remember much. MC is a coward. Ran away to a mountain after discovering that his childhood friend found a lover and broke their promise. A Goddess took pity upon his cries of sorrow and *gifted* him untainted powers. MC is a monster, quite literally as his race is unknown from whence a human. Unknown to him, another him summoned, acting as a Hero to sloo the Demon. Along with this summon, a harem follows him, along with his long, long, childhood friend who promised a broken promise. Also, did I forgot to mention that this "harem" has the MC's girls in it as well? Rip.