Upon being arrested for the gruesome murder of her father, all college student Kanna Hijiriyama tells the police is, "It's up to you to find the motive." Amidst the media frenzy about the woman "too beautiful to be a killer," clinical psychologist Yuki Makabe is asked by Kanna's lawyer to counsel the young woman as her trial approaches. Yuki slowly uncovers the dark history behind the relationships in Kanna's life – with her father, her mother, and her "first love" – and discovers shocking inconsistencies in Kanna's defense.
Winner of the prestigious Naoki Prize and a Japanese bestseller, First Love is part psychological drama, part legal thriller.

Rio Shimamoto was born in Tokyo in 1983. In 2001, she won the 44th Gunzo New Writers’ Prize for Silhouette, and in 2003, she won the 25th Noma Literary New Face Prize for Little by Little. In 2015, she received the 21st Shimasei Renai Literature Award for Red and the 159th Naoki Prize for First Love in 2018.