Review Detail of Gratiz_ in DxD : Conquer Multiverse

All characters are braindead, mc included. Also his backstory - 16 year old summoned by a demon to become a demon hero wants a harem, then he is possessed by a demon and dies after untold amount of years with the demon. Okay, now that he is dead he wants a harem... Chaos goddess helps him to reincarnate in dxd, mc is obligated to make her his first harem member. Thanks no thank you. It seems the author is braindead too. If you want a harem at least make it realistic. What's the point otherwise?