Days With My Stepsister, Vol. 4 (Manga)

Yuuta and Saki have decided to hide their feelings for each other away, choosing instead to live as brother and sister. But suppressing their emotions isn't easy, and even as Yuuta tries to turn his attention to other women, it only makes him realize how special Saki is to him. And Saki, for her part, isn't faring much better…