Welcome to the edgy revenge genre, where the MC won't just take ages to kill all their targets, but will even make new ones along the way to stretch the plot even more :')
It's actually nice that MC doesn't only build a giant harem (they wish at least to be part of his harem), but also has a couple of cool guys on his side :P
The author is probably the final boss once he killed all gods, everyone who made his life hell and everyone else who looked funny at him once, or coughed in his general direction.