Tenjou No Niji summary:

Prince Naka-no-Ōe showed his interest in the talent and beauty of Nukata. He then offered Prince Ōama his daughter for marriage, in exchange for Nukata. Prince Ōama was in agony as he was devoted to his brother but in the mean time, he loved Nukata. In the end, he chose to let go of Nukata as a gesture of loyalty to his brother, however heartbroken. This was the beginning of the long and epic series of Tenjo no Niji, in which Princess Uno-Sarara, Prince Ōama’s then young bride, would become his ally in succeeding the throne and later made herself Empress Jitō…..