Devon's historian let him know about Ken and what he had done with Lensa, including what he had said in the end. Lensa's young uncle was incensed after knowing her niece's heart was broken cruelly by this wretched human.
The fact that he was under the booze's effect didn't lessen Ken's involvement and responsibility in the situation. Devon would make sure to punish the guy who had forced his lovely niece to cut her connection from the rest of the world in such an extreme manner.
Devon left out the part of Lensa caging herself in the block of ice using the magic of unknown origin and told everything else to Almera and Eren. The fact that such a reclusive expert had called to preserve that ice from getting destroyed hinted to Devon that he should keep the spell-generated ice block a secret for now.
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