Girlfriend, Girlfriend Vol. 15 (Kodansha, 2023)

Things are looking rocky for Naoya and Nagisa when Saki proclaims that she can no longer be part of the polygamy. When faced with Saki's question of whether she preferred a normal, one-on-one relationship or this two-timing thing they have going, Nagisa comes to her answer… What is Naoya to do now that Saki has finally accepted Nagisa's feelings and her own conviction begins to falter…?