So Bad!
From DGT: Since Yukino's mother is a set of Rengio's family, she must suffer from pain, listening to her mother praises the family that she cares about. And that is why Yukino tried to defeat Rengio Tamaki most of his life, so her mother will take care of her more than about the family of Renjio. But when her mother is ill, and instead she has to take care of the family of Renzho, her goals change a little.