At first I actually thought Aoi was cute even though I was on the HildaOga side. But then as the series progressed, I kinda start thinking that Aoi's misunderstandings became annoying and redundant. And then before I knew I was skipping her parts in the manga..@__@ I don't think I hate her but rather.....I'd like to see her without that stupid crush on Oga..sadly, half of her appearances had something to do with that infatuation with Oga.
Hilda on the other hand is very cool, mature, kicka$$ main heroine and someone who can really keep Oga in line. I like her devotion to baby Beel and I was sold with the pseudo-family theme that they have from the very beginning.