I know at this point rereading this is the best option but can someone TL;DR the past or something, I only remember our hero being the possible reincarnation of some hero of the past, and the three girls are from the old hero's party, and they are collecting something? IDR what they were collecting, but they went to the dragon girl's kingdom and heaven, and this thingy invaded heaven but IDR why and who are the guys that made this thing and who was the dude the mc fought in the last chapter.