This doujin kind of felt like a series of deleted scenes, more than anything more coherent by itself? It's an interesting idea, but rather than adding in extra context or revealing some hidden side to anything, it just felt like "Oh, right, these scenes were cut for time because they were mostly unnecessary, that was Good Editing".
Also, I tried looking up flower meanings to see why blue and white anemones would be significant, but what I got was that one means death or misfortune and the other means anticipation of/protection from evil? I'm not sure that's quite what they were going for, but at the same time, it kind of fits? Flower meanings are weird.