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Abstinence, Failure. ~Living together with a beautiful, defenseless, zubori-style woman, the theory is that 30 days is the limit of how long you can hold out for sex.

Under one roof, the sensitive body of a defenseless older beauty trembles with every caress... Tonight, I won't let you sleep until you make me cum for 30 days...!
--Shun is staying with his relative Satsuki, a lazy female office worker, when he goes to college. They start living together in a small one-room apartment separated only by a piece of cloth, but Satsuki is full of openings, wandering around without a bra, rolling around in her erotic underwear, and so on.
On the 30th day of living together, Shun finally loses control of his sexual desire, but Satsuki is also masturbating on the other side of the partition...?
Isn't it enough to just have sex already?" Unable to resist, Shun sucks on Satsuki's tight hole....