Transit Girls is the story of Sayuri and Yui, two girls thrust together by their parents’ marriage. Sayuri resents the intrusion and doesn’t believe that anyone could be a replacement for her late mother. And she certainly doesn’t believe that she needs a new sister. Even though Sayuri is cold and distant, Yui tries her best to help her warm up to the idea of being a family. Overcoming every reservation she used to have, Sayuri falls in love with Yui, who was smitten from the day they met. But there’s one big problem… no one can find out.