I moved in with my brother and sister-in-law Nao Jinguji for the convenience of going to school and work. Living with both of them, I often had to witness their intimate scenes. Even though I was right next to them, they still did things that should have been done in their own room. As a boy in puberty, that made me feel extremely lustful. My sister-in-law often wore very sexy clothes at home, which made my lust grow stronger and stronger.