I don't know whether this has ever been brought up or not but i heard something about there being a super boss after u defeat all the dark aeons, is it true? i've only got anima, bahmut and the magus siters to go and i don't want to waste my time if theres nothing after them.

Yeah, there is one. His name is Penace. I don't know much about the Dark Aeons and stuff cause I only have the US version, but you should check out a FAQ on the Dark Aeons for more info and stuff.