DVAJ-438 A week of daily intense training with non-stop semen explosions to toughen up my five-minute wonder little brother, courtesy of my sister-in-law. Nanae Kawakami

I was troubled by not being able to satisfy my wife due to premature ejaculation and was practicing with a fleshlight when I was caught by my sister-in-law, Nanami. After explaining the situation, Nanami offered to help me overcome premature ejaculation. From then on, days began where I would sneakily train my penis with Nanami's handjob. Nanami, in her enthusiasm, escalated the acts to kissing and fellatio... eventually even promising that if I could last 15 minutes, I could insert it into her vagina. Let's see if I can hold out and insert it! But if we combine, it would count as cheating... Ahh～I want to put my penis in my sister-in-law's vagina and release all my semen!!