Intimate Days with My Tsundere Sister

She and I are left utterly alone in our quiet house.
In the dead silence of the residence, a sweet, dangerous tension begins to thicken the air.
She, usually so cold to me, reveals a completely different side of herself when it's just the two of us at night.
Her lovely sleeping form, wrapped in loose pajamas... The soft swell of her chest and smooth, white skin peeking out--the sight makes my groin ache and my pulse hammer in my throat.
With every one of her defenseless, sweet breaths, the forbidden desires I'd long suppressed began to throb with a raw, desperate need.
"I can't... I won't hold back anymore..."
My uncontrollable lust reaches its boiling point, and I finally resolve to break the ultimate taboo -- to defile her and make her completely, utterly mine. But this summer, it seems it's not just her; other tempting women are aiming their own lewd designs on me. A one-month limited cohabitation -- can I possibly contain my pounding erection as I drown in depravity?
The clock is ticking--only one month. The story of a forbidden life of secret passion begins now...