As in the name of the anime, it is about a Russian girl transferring a high school in Japan. I think the director of this anime has never seen a real Russian girl in his life. Especially Kujou is the most anime girl I have ever seen in my life. Just speaking Russian can't make you a Russian. It is a good anime anyway, but I think they ruined their potential. Also, the brother complex of Yuki is a little bit scary.
If you liked the series like Nisekoi or Kaguya-sama, this anime combines both. The student council and forgotten childhood love...
It is worth to watch if you don't have high expectations.