Review for Twice
I really like this story; you do a really great job of encapsulating their entire relationship within one vignette.
For the first paragraph, I think the main problem is the first sentence; you could change it to something like 'Shunsui still remembers the first time he saw her sword' in order to incorporate it more fully into the rest of the paragraph, or simply cut it out entirely. Still, I'm not sure if I would have noticed that if you hadn't mentioned it in your author's note.