I live alone and by chance I'm dating two married women. It's a two-timing affair. Ai-san is a tsundere older sister type, and Misato-san is a baby-faced pretty girl. I couldn't choose between them, and I was getting along well with them... but then something happened! Ai-san and Misato-san double-booked me! And so, a fierce battle began to break out over me, and I was so cornered that I ended up hospitalized with gastritis! However, the battle between the two of them just got more and more intense...