I work in IT and live apart from my wife, whose job keeps her away on long business trips. On her rare visits home, she demands sex as if venting all her frustration, leaving my own stress and desire to build by the day. Her adult sister Sumire and I are close, and she often visits while my wife is away. One evening, as we drink and chat like usual, Sumire suddenly kisses me. With a teasing smile, she whispers, “You can have the rest if you manage to abstain for a month...”