I think hes an ancestor
He’s not their dad, but he is an old relative given that he was just a kid in Lucas’ original timeframe and not yet king nor most powerful magician when Lucas took his long “nap.” He resented Lucas for turning him down to being his teacher for magic, and along the lines, somehow, I assume he never died but preserved his soul with dark magic(?). He corrupted Anastacius before he died after Claude stabbed him.
He is an ancestor,,, if i am correct he was mentioned in the previous chapters as the "strongest emperor" and he was supposed to be a student of lucas but lucas called him a weakling and the humiliation aeternitas felt might be the reason for him to hate lucas so much (idk if there is a deeper reason)
hes the most powerful emperor in obelian history
I know Aeternitas but, how is he related to claude and athanasius, is he the father of those two?