I'm...a bit confused but also feel like crying at the end.
This, along with the other one (Foolish Tengu Raid), are probably one of Yakumi Sarai's most normal books, but this one is quite emotional.

Mix emotion is normal! Have a blast!

I approve of everything contained.

@Clover, I don't know what confuses you, but I'll give my understanding of it.

The manga depicts scenes as Remilia experiences them. On her actual birthday, she's looking at her own "fate". She's dressed in black and she enters each room using the keyring. When she enters a room, a piece of her fate is shown. In this case, they're all of the 'birthdays' Sakuya held for her. She describes herself as a spectator, and a comparison is made of watching her fate like one would watch a movie. That's how little control she feels she has over her own story, to the extent that what she manipulates is only what scenes she watches.

She says that fate is timeless, and yet she starts wondering 'what time' a certain moment happened. Sakuya is the one who points out her sense of timelessness, which in extension is how stuck she is, and after viewing the third birthday party (from our POV), she runs everywhere to see the portions of her fate which are connected to Sakuya's, seeing the passage of time through Sakuya. This leads her to realize despite fate being "set in stone", she doesn't want to just accept Sakuya's death as another matter of course. Watching Sakuya on her deathbed is enough to make Remi cry, which is when Sakuya catches up to her. She takes the keyring and gives Remi a watch, symbolic of having time move forward for her. We then see Remi's life play out sequentially, as Sakuya's had been before. And at the end, she has embraced the passage of time and her ability to "control fate".

In essence, Remi had been stuck in time, Sakuya rescues her, and Remi becomes the charismatic child seen in Touhou, seizing her own fate, actively living instead of passively watching.

I see, thanks river! I get the gist of it but I'm doubtful, so...

@Clover, I am curious as to what you're doubtful of.

Related to the afterword, I thought Yakumi's thoughts were interesting. I'd thought of those "sure things" and themes of past "great works" as being self evident and the best of Touhou fanworks. But that's because I've been exposed to them through archive crawling and there's a humongous archive on Dynasty/other places which goes back quite far. Either way, I like the way this person thinks. RemiSaku is a sure thing. ;)

Was going to complain about another Sakuya x Rem fanfic but saw old Sakuya got hit by feelz train ;______;

there is a small error in pg 44/45 that was fixed https://mega.nz/#!zQEGHCwY!DA1KeWj5q4NCTvkwxTG3YpZoPjgTQaZ6PPF9gXAATRk

I think its confusingly structured- I think it needs to be made clearer if you are gonna jump about timelines /fates etc like this.

Also- it contradicts itself when Remi says she cant change or manipulate fate at all, then on the next page says 'this is her power to manipulate fate' ? What is? either she can change it or she cant- because just watching bits of it at will is NOT manipulating it..

Its also cannon - as far as i know- that Remi DOES in fact manipulate fate- but that, I think- she doesn't have conscious control of it?

I feel like it's meant to be disorienting at the beginning, since we are suddenly jumping into a random point of her life. After page 10/11 though, it's clear what's going on, that she's walking room to room examining her fate.

For supposedly contradicting itself, I interpreted that as dramatic irony. Her official ability is "manipulation of fate". What that means is never expanded on in any official works so it's been left up to fan interpretation. So here, in the first half of this story, Remilia's power to manipulate fate is depicted as being powerless, passive, only allowing her to manipulate the order in which she views her fate happening. The dramatic white text against black background provides a sense of contrast and the text leading up to it on page 15 pits her supposed ability to manipulate fate against her helplessness. Which is why at the very end, the definition of her ability to manipulate fate is flipped, now highlighting that she does have control and the ability to live in the present.

Again because all we know is that she has the power to manipulate fate plus her few appearances in the manga serializations, whether she has any conscious control over it is up to fan interpretation.

I'm a bit confused on the sudden transition to Touhou 6 event.