[From Lililicious]:

Pure Shadow is a darker story about two girls who consider double suicide together

Ureha's boyfriend proposed to her three months ago, but she hasn't given him an answer yet. While visiting a cosmetics shop, she sees a woman, Sawori, who suddenly makes her remember a lesbian experience from high school. She's not sure that's something she wants to repeat, but will she be able to resist Sawori's advances?