Responses
I've been thinking it might have been that uncle of hers...
Honestly it’s really likely it would be an uncle, I also hope it is. I think either, MC’s dad knew of the uncles doing and took them in as showing sympathy or it’s as the story goes and he was just sympathetic of their situation and is oblivious to him that the villain is the his brother (uncles) daughter.
I've been thinking it for a while, but what if Meryl was tricked by someone who looked like count Grint? What if she isn't a psycho woman, but is actually a scorned woman who was used by either Count Grint's secret brother/relative or someone who resembles him? This obviously doesn't excuse her actions, but it would make more sense cause ain't no way that MC's dad cheated. Plus we just saw a glimpse of someone on the other side who had blue hair too, which makes me even more suspicious...