Gohoushi Sister! Sophie & Patty

Before Masahiko Shishidou, a student preparing for university entrance exams, appears Sophia—a stunning silver-haired beauty.
And then, Patricia, Sophia’s younger sister and Masahiko’s childhood friend.
With their father’s blessing, the two beautiful sisters become Masahiko’s fiancées, setting the stage for a steamy and intense battle of seduction.
The fight to win Masahiko’s heart—and more—has officially begun!!

[Translated from dlsite]