Kentarou's summer takes an unexpected turn when his beautiful Aunt Shizue returns to town for a visit. After discovering Shizue's secret promiscuity at a local shrine, Kentarou finds himself drawn into a passionate encounter with his neighbor, Rumi. The night culminates in a daring sexual awakening as the three of them share an intimate connection under the summer sky.
Shizue visits Nobuo at his photo studio, where he is photographing his wife, Ami. Shizue encourages Ami to embrace her sexuality, leading to a provocative encounter between the two women that Nobuo captures on film. The professional atmosphere quickly dissolves into a wild group encounter as Nobuo joins in, eventually involving Kentarou in a scene of unrestrained passion.