Unbeknownst to her brother, Akane had grown into an adult and learned lewd things. She started bringing home middle-aged men older than her brother. Believing her brother was out, she engaged in lewd acts with a middle-aged man in her room. Her brother, who had feigned his absence, peeked into her room and saw her having sex with the middle-aged man, becoming aroused. The action Akane took towards her brother, who had been caught peeking, under the condition of keeping quiet…
