At this point im only continue reading this series bcoz of Pochi.
Also if they are trying to make this series into anime, i think the VA for Irene is the same as VA for Tanya Degurechaff from "Tanya Evil Saga"
This MC being smart and dumb at the same time... But mostly dumb. He just live for 5k years for gaining knowledge yet dropping some of them too... It's like he is useless, been living 5k yrs for nothing....