My Wife Is Unreliable: A Matriarchal Society

Qin Moyan never imagined that, as a son born of a concubine, he would one day be cherished and doted on by someone. Spoiled, spoiled, and spoiled some more, he was pampered until he became utterly unruly. So when his legitimate-born elder brother came to demand why he was allowed to be with Su Xiyu, he could calmly reply, "Sorry, but weren't you the one who cried and begged me on your knees to marry in your place?" Regretting it now? Too bad. It's too late... [Turns out you're even better than I imagined] In a nutshell, this is a simple story about an unloved son born of a concubine who takes his legitimate brother's place in marrying a supposedly cold and ruthless young general, only to unexpectedly find his own happiness. I'm no good at writing palace or household intrigue, so besides sweet, sweet, sweet, I really don't know what else to write ←_←