The story spans between 1863 and 1868, something we know because the first and last scene are the same and there's an indication that the story begins five years prior, but if not for that the story could all as well happen in the span of a few months or weeks because the characters don't show any visible differences (i.e. hair growing, different clothes). There's also no real explanation of what's going on, you're supposed to already know who Ryouma Sakamoto was, what he did and the whole historical background for the story to make any sense, there's no outside narration and the dialogues give only a few hints that are hard (if not impossible) to put together with no prior knowledge.
Characterwise it doesn't get much better, Ryo does have some growth in that he goes from being shy to become more outgoing as he stays with Ryouma but even that is poorly handeled, I guess it's a way to show some time has passed but it still does come a little out of the blue. The other characters are almost all really existing people so they have to be there but otherwise they're as hollow as they can be, with (again) no proper explanation behind their actions.
The animation is without doubt the best thing this short has to offer, the action scenes are fluid and easy to follow, while the character design isn't anything remarkable and the background characters tend to look very similar; the background music too isn't anything special, while the ending sung by Hitomi (the one that made all the songs in Code Geass) is nice but doesn't fit much with the tone of the story.
In short, had this story been developed in a full 12/13 episode series it could have been a good addition to the many anime that feature the Bakumatsu era, since (to my knowledge) most focus on the Shinsengumi or only use the historical period as a background and as such it would have been a good chance to see the other side of the story, but by trying to cram too many things in such a short time it actually backfires and leaves the watcher with more questions than answers, one above all: how does the clash between Ryo and Hijikata go? Little spoiler: Hijikata dies in 1869.
