Yua has hated her father-in-law Taku since she got married, she has no choice but to accept the situation and the bastard, and resorts to drinking more and more wine.
Taku himself is a retired out-of-touch guy, rustic and vulgar, but he still likes women and appreciates Yua’s superior beauty.
He takes advantage of her son being on a business trip to make a definitive approach. Took some convincing and spiking her wine but he finally succeeded.