Miki Sunohara is asked by her respected teacher, Kururugi Mikan, to become a sketch model. Delighted to accept, she soon discovers to her surprise that it involves nude modeling. As she is instructed to strike various poses and her tension steadily builds, she is suddenly shocked by an unexpected kiss. Kururugi's snake-like tongue forcefully invades Miki's mouth, gently yet powerfully exploring her, and the intense heat makes Miki lose all self-control.