Tsujimura is an award-winning novelist, she is best known for her mystery and children novels. She studied at Chiba University and won the Naoki Prize in 2012 for Kagi no nai Yume wo Miru (I Saw a Dream Without a Key), and in 2018 she won the Japan Booksellers' Award for her novel Kagami no Kojo (Lonely Castle in the Mirror).
It is a quick read, the story goes with a smooth pacing, I don't like how the female friendships in the story are projected here (a bit too stereotyped and predictable, I guess) still I admit there is some truth in what the author had described between these three young women and one of the women's boyfriend. 3 stars only.
PS: and the book's cover is so breathtakingly beautiful and imaginative!