Nee♥Summer! Nee♥Sama!

Yuuta is in his final year of high school, and with college entrance exams looming, he plans to spend his summer break buried in his studies. His older cousin, Kei, offers to help him prepare, presenting it as a favor to keep him on track. Grateful for the support, Yuuta accepts, expecting long days of quiet review and practice tests.

However, Kei's idea of studying together turns out to be very different from what Yuuta imagined. Her presence becomes increasingly distracting, and the boundaries of their cousinly relationship begin to blur. What started as a simple arrangement quickly turns into a summer of unexpected temptation and forbidden desire, as Yuuta finds himself caught between his academic goals and the allure of his cousin's advances.