Magic Filter
I don't really know the whole story, just bits and pieces from what Emma's told me. I'll have to admit, I'm not a fan from what I know. But from everything I was reading, it does sound like she was taken advantage of. Of course, there's always the chance that more information will come out later that proves otherwise, too.
It wouldn't be difficult. I would just have to get close enough to him to do the spell. It wouldn't take long.