(I... I can't take it anymore...! With this guy's di*k inside me...) Saki is a busty high school girl who's a bit of a delinquent, but values her friends deeply and hates anything underhanded. To protect her close friend from a sleazy old man who claims "paid dating" is his hobby, she accepts a shameless challenge: "Whoever cums first from sex loses!" Though confident in her physical strength, Saki has zero resistance in that particular area. Skillfully manipulated by the sugar daddy old man, she loses her virginity and is made to cum, and even her precious first kiss is taken... Huh? This old man's tongue technique feels incredibly good... To win the challenge, she faces the old man again and again, but each time she's overwhelmed by his masterful techniques and ends up cumming over and over. Eventually, Saki starts seeking out his di*k herself... What will tomorrow bring for her...!? This is how to make a strong-willed girl submit! Dedicated to all JK maniacs, a 20-minute guide to "the correct way to rail a high school girl"!!