Basically, you're buying the last two episodes of One Room Season 3, and like others have said, you'll get a summary of what happened between you as the MC and Yui up to the very end. Hopefully more characters would be added one day, though it would be nice if they added some new contents on top of what we already seen in the anime, like an exclusive VN style story with the ability to name your protagonist.

Either way, I'm glad we gotten something like this, as it was nice to revisit the world of One Room ever since Season 3 ended.

For those who have already seen the original One Room anime, I would recommend getting this for a quick trip down memory lane. For those new to One Room, check it out and see for yourself, you might come to love it!