. Sayphus, you are fairly new (welcome), but next time please ask I.D. questions in the links found under "Identification Help" from the home page (beneath "Help & Guidance"). And since you are asking a potential helper to give up precious time to lend you a hand, it would be nice for you to spend some time by providing reference. For example, if you own the movie, making a few frame grabs of clear views of your lady's face would not only help, but it would increase the odds of getting an answer.
From the back cover, the lettering underneath and beside each lady might provide clues for the actresses... but for that, a knowledge of Japanese would be handy. I see JavLibrary has one cast listing, for Erika Kitagawa (A.K.A. Yuria Sonoda, Mei Hosaka). If luck's with you, perhaps she is pink hair.