I don't know if he know for her life in korea. But yeah he know that it is her second life as Athy.
I don't think Claude can reverse time with black magic... It's Athy's magic.
Maybe he was trying to ressucite her ?
Resurrect her mom is more likely
yes, he used black magic but
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he used black magic to forget diana bcs at novelupdates it stated that claude killed diana bcs diana requested him to. athy has a magic to reverse time so when claude saved athy when athy's magic exploded, her magic affected claude
So here’s my theory, so her first life wasn’t her but the Athy from the book who died by being hung? Then you have the Athy from our world (I’ll refer to her as Bathy haha) who I’m guessing died form overdose, in Bathys world Athy is but a story but then when bathy died she became Athy and so that’s why the magic dude with black hair sees all three of their lives. Maybe when bathy woke up in Athys world, Claude could have reversed time to when Athy (bathy) is born but hasn’t remembered doing it cause it’s black magic, maybe he was trying to reverse time to when Athys mother was still alive but couldn’t go that far? Idk I could be completely off the mark lol