I was aroused when I saw my sister-in-law's body at the hot springs during a family trip. My sister-in-law got hot when she saw my erection. Of course, she secretly had sex with me without my brother's knowledge. SW-248

The elder brother and his wife arrived at a hot spring inn. During their travels, the elder brother's wife's subtle allure captivated him. At the renowned mixed-gender open-air hot spring, he saw her body for the first time and became aroused. Unable to resist touching her, he noticed her trembling with excitement, despite her seemingly serious demeanor! Thus began their secret sexual encounter, one they couldn't tell the elder brother…