I'm so sad for the youngest mage and Hermann, if only they met in the right circumstances ...

And clearly guys she didn't groom him, she didn't see Hermann as something else. He's always a child to her, i think if i remember right she even said "poor child" when they were talking before she was captured

Technically, she did. Perhaps not in a "I like kids" way but she definitely manipulated him mentally into taking the role of (what I would describe as) her servant in a sense— which counts as grooming.