Well, for starters, this movie is an alternate "what-if" scenario in which things could have gone differently. But we all know how fate goes, so despite an alteration in events, the outcome must ultimately always end the same.

Yukito, I imagine, showed up to town a lot later than he had in the original timeline. The festival was only a week away, whereas in the anime series he was long there and long gone by the time Misuzu went with her mom.

In this timeline, it's clear to say that Misuzu is the one to have lived a completely different life, and that is solely because this is the universe Haruko wanted in which she was a mother to Misuzu her full life from the moment she adopted her to the moment of her death, and I think you can see that rather clearly and not just by the obvious matter.

Misuzu, in this universe, is a far more free-spirited person; she was raised with so much love that not only did she get sick and begin withering away far quicker, but she had the confidence of having been loved so much by Haruko that she was able to throw her arms around Yukito and tell him that she loved him, something she was incapable of doing in the original timeline because of obvious insecurities. After all, Misuzu in the original timeline first of all lost her mother at too young of an age to have remembered any kind of love from her, her father casted her away for the sake of her "health" and nobody wanted to take her in, and so Haruko was forced to and restrained any kind of love or affection towards her. So then, when you've got a girl who has not been shown any kind of love in her entire life, a girl who has no friends or any form of a companion because they always leave when her sickness intensifies and they call her weird...

How on earth would you expect Misuzu to believe that anyone, especially Yukito, would be capable of not only staying by her side as a friend, but as a lover?

In this timeline, however, Misuzu is far more sure of herself than she ever was in the original series. She receives all the love in the world from her mother Haruko, a mother who actually acknowledges her; it was so heartwarming to see Misuzu's bedroom full of all this dinosaur decor that had likely come from all of those presents Haruko refrained from giving to her for all those years her birthday passed by. She is just so full of love, not just to give but ready to receive because even though Misuzu knew all this love would lead to her death, she still cried in her mother's arms and told her that the heartache she had to endure for so long in the original series was far too excruciating to bear compared to the physical hurt of having those she loves close.

I also feel we learned a lot about Yukito as well from this movie, especially along the lines of how he really feels towards Misuzu because that was never really a subject that was breached in the original series. Yukito is a wanderer, an avoidant lover at his core; when he began growing genuinely attached to Misuzu and realized that she felt just as strongly for him, his first instinct was to run away because being around other people is something he has expressed of being scared of. Not only does he shy away from crowds and public spaces (aside from his work, of course, that is garnered towards children; he says it himself that he hates people because they lack so much genuinity, but with children, they just have a way of being far too honest). Misuzu, as well, has that child-like soul and spirit where she's not only so warm and kind and giving towards other people, but her happiness and joy towards the littlest of things is just far too genuine, and I think that's what made Yukito so close and comfortable around her so fast.

And that closeness, of course, was what made him fall in love with her.

The closeness of Misuzu and Yukito was something I especially took notice of throughout the film. You realize that Minagi and Kano never did cross paths with Yukito, and I think that's a very important fact to consider here. During the anime, Yukito began spending less time with Misuzu but instead with Kano and especially Minagi to a point that Misuzu was getting heavily neglected; you could notice in certain scenes where she would be lurking around corners and watching from a distance, and eventually when Yukito does return to her, that is when he realizes that she had already begun to fall ill.

In Misuzu's case, of course, I genuinely think in the original timeline she did have feelings for Yukito, but because of what I explained above of having never been loved, she hence believed that she was destined to be alone and never deserved that in return. And because of that, Misuzu never shared her feelings with him. As for Yukito, I don't think he considered having any kind of feelings towards Misuzu until Haruko had up and left and he was left there in that house taking care of Misuzu all on his own, and I think this is because so much of his time was preoccupied helping Kano and Minagi that he just didn't get to spend enough with her to really fall hard like he did in this movie. But just like in the anime, Yukito once again tries to run and ends up coming right back where he belongs, but instead of having his soul combined with Ryuuya's within the crow, one thing that is different about this outcome is that Yukito is kept alive whereas Misuzu meets her inevitable fate once again. This part of the story rather confused me a great deal, since Ryuuya had also died with Kanna in the backstory, but part of me kind of theorizes that Yukito dies not too long after the end of the movie.

All in all, I think this movie explained a lot of things, especially in the way of Yukito and Misuzu's feelings towards one another. I absolutely loved getting to see those two pine away for each other, and what few little moments they could bask in that love for one another before it was forced to once again be torn away from them. While it doesn't have to be an essential watch following the competition of the anime, I think it really helps us to better understand the connection that ran between the two leads.