Gorgeous addition to the show. It was super sad and lovely. I think I loved this episode more than the show. It was a perfect add on, a behind the scenes look into Mei's background before the terrible day her sister passed...honestly, if they would have went into some other character backgrounds on the show, or even implemented this one in as an episode during, it would have given the show much more life. I understand Mei much more now.
Overall, great addition. 7/10.
Watched - subbed