In order to prevent the villainous princess from bringing doom upon this world, Jiang Xu—who transmigrated into her imperial sister-in-law—does her very best to nurture Her Highness into a virtuous and well-behaved ruler, despite her own frail health. However, when she grew up, the haughty yet alluring princess unexpectedly pins Jiang Xu down onto the bed.

"If you can love my brother, why not me, too? Won’t you have a look my way, my dear sister-in-law?"

Jiang Xu: …If you think I’ve lived long enough and want to drive me mad, just say so!

(Source: Bilibili, translated)