Not biologically related / no blood ties / not registered in the same household.
There were two young ladies from a wealthy Kyoto family. Both excelled academically, and both were refined and dazzling: one was a vibrant, blooming rose, the other a cool, luminous moon. They were the sort of people outsiders could admire from afar, but never approach.
Later, one became a ruthless businesswoman, while the other became a reserved, ascetic professor.
But only a few people knew the truth.
The younger sister was the heiress. The older sister was brought into the family by her stepmother when she remarried. They were worlds apart and had a terrible relationship. Neither could stand the other.
Then the family fell into ruin. Their father jumped from a building, and their mother ran away.
The younger sister, a beautiful girl who had been spoiled rotten, was chased by creditors and got into a car accident.
A friend asked the professor what she planned to do.
"Nothing," the professor replied coldly.
Later, the heiress vanished without a trace. Everyone assumed she was dead. Then the professor changed careers, and the wealthy family was no more.
One day, while on a business trip, a friend passed by the professor's house in the suburbs and stopped in to visit. There was the younger sister, sobbing so hard her face was streaked with tears, clinging to the professor. The professor gently wiped the tears from the corners of her eyes, and the younger sister hugged her, demanding a kiss.
So it wasn't that she didn't care. She'd been keeping her hidden away all along.
The younger sister had lost her memory, and the older sister had brought her home. The younger sister called her "Big Sister," but kissed her ear and called her her wife.
She raised the gorgeous rose who lifted her face to the sun, the proud peacock who thought herself above everyone else. She watched her cry for her, watched her cling to her with tearful eyes and beg to be comforted when she came home even a minute late. She taught her to love her, to depend on her forever, and to embrace and kiss her.
And she made sure no one would ever know.
That spoiled rose from the wealthy family had long been coveted by the moon.
The despicable older sister played the villain and kept her rose captive.
She hoped the rose would never bloom, that she would remain a bud forever.
Of course, like in every cliche story, the rose would eventually awaken in the daylight, beyond the moon's reach...
*
"Who knew the older sister, held up as a paragon, was hiding such a vile desire? Shouldn't an older sister set a good example?"
Theme: Stay positive. Every flower will bloom, so never give up.