“Does Mai remember Yuuichi? Is she secretly hiding a grudge against the man who doesn’t seem to remember the past, or is she honestly experiencing being cared about for the second time (Sayuri aside)?”

Mai did remember Yuuichi as a child, but didn’t know that the older Yuuichi was the same person as the boy who left her 7 years ago. You can argue that subconsciously she might have known, but consciously she thought of the older Yuuichi as a different person, up until the point when Yuuichi confronted her.

“How long have the demons been around? Has Mai really been fighting all these years? Or is it something that’s resurfaced with the reappearance of Yuuichi?”

I believe the demons/monsters started appearing right after Yuuichi’s phone call telling Mai he’s leaving. At the time, the demons were the demolition tractors that ate away the field they played in. Eventually they transformed and materialized from Mai’s power, fuelled by Mai’s self-hatred. Mai had probably been battling her own monsters all these years, but the intensity of the battles might have increased with Yuuichi’s reappearance (Freud would have a lot to say about Mai’s repressed memories lol).

“What ‘control’ does Mai have over her demons? Why do they attack Yuuichi – or do they? Is it intentional? Could Mai just want to be the hero that protects Yuuichi, protects Sayuri, that saves the day?”

The demons didn’t just attack Yuuichi. They also attacked Sayuri and Mai herself. I don’t see Mai’s intention to be “protecting her friends and being the hero”. Rather, the demons were a direct manifestation of her self-hatred, which appeared when she thought her powers were what drove Yuuichi away. Since then, she started literally attacking the side of her that she despised the most, all because of a simple misunderstanding that happened 7 years ago. Mai’s story really puts a new twist on the phrase “Your biggest enemy is yourself”.

(As you can probably tell, Mai is my favourite character in Kanon. She’s got a little bit of all of us in her, which is why I care about her story so much. That and I love psychology~.)

Could Mai just want to be the hero that protects Yuuichi, protects Sayuri, that saves the day?

Yeah, you said it was a hypothetical question, but I really feel you hit the nail on the head with this one, especially in relation to Sayuri. I’ve always felt that Mai wants to protect her as a way of showing thanks for Sayuri’s friendship (that, and yuri love!)

I prefer to call this sort of thing a ‘fanboy paean’, not a ‘fanboy rant’.

And now, if you’ll excuse me, I’m off to watch something non-Kanonical.