Sex Sl*ve Widow-Sisters Forced into Animal Sl*very / Miharu and Miku's Sl*ve Diary

Miharu Sawaguchi is an energetic, healthy girl who has been brought up in a very privileged household. She's a very beautiful, charming young girl who men cannot help but be attracted to. Miharu has been blessed from all around, and she finally finds the one man she should love, ties the knot with him and becomes his wife.
However, her happiness is brittle and it soon crumbles away into nothing.
Tragedy strikes the newly-weds and the new husband Yosuke quickly passes away.
The youthful and spirited Miharu becomes a widow at the tender age of 23 years old.
Having lost her beloved husband, Miharu passes through the days vacantly, with no sense of meaning.

One day a man named Akihito Suyama comes to visit Miharu.
He informs Miharu that her deceased husband actually left behind some debts...