The Boundless Ocean. Volume 4

On a stormy night, Iori and Tisa find themselves alone watching the house. But they are unaware that a passionate, libido-filled evening is about to begin. Meanwhile, Iori's younger sister, Shiori Kitahara, appears, turning Kohei into a jealous god of destruction.
Summer vacation is just around the corner, but first, the guys must overcome the madness of lectures, reports, and lab work. After all, university is a place of study. But if you thought the professors at Idzuru would be normal, then another surprise awaits you! It’s a deadly duel against the associate professor, with both pride and academic credits at stake!..