The Sword and Heir of Shadows - Chapter 22: Grim Determination.

Based on the popular Vocaloid series, by HoneyWorks, called “Kokuhoku Yokou Renshuu (Confession Rehearsal)“:

Natsuki, a third-year at Sakuragaoka High School, who holds unrequited feelings for her childhood friend, Yuu, who’s in the Film Club. However, instead of being honest about her feelings, she makes him be her confession “rehearsal” partner. Unable to say her true feelings, things start to get complicated when Miou and Akari, who are also in the Art Club, get involved! Will she ever be able to confess for real!?

Once she transmigrated over, Li Haitang, an elite female doctor from the big city, is demoted to a pitiful little cabbage whose parents have both died. She is surrounded by extreme jackals, wolves, tigers and panthers family and relatives. What? She is sold to a half-dead body that is going to be buried in the ground. Has she been sold to an old man with a heavy taste? The only way to escape from the arranged marriage is to pack a bundle wrapped in a cloth! Who would have thought that on the way to the wedding, she meets a wild man who is feared by everyone in the village? The wild man has three treasures, he is hardworking, spoils his wife and has good stamina! His pectoral muscles, abs and mermaid’s line are all there.

Senior high school student Dugu Hong was logical autistic and had a very high IQ. Despite his impressive IQ, he was never taken seriously by his teachers or schoolmates. While playing a recently released eastern Wuxia online game called Jiang Hu, three vicious classmates trapped Dugu into a mountain cave in the game with no hope of escape unless he deleted his account and re-register it. Not succumbing to their demands, Dugu decided to stay in the cave and explore the game system, which benefited him greatly. His persistence to obtain massive internal strength aided him in finding a superior way to improve himself, and thus opened the function of inner observation of the main and collateral channels. Meanwhile, in the real world, he discovered he had supernatural powers when he tried to save the girl he secretly loved who had caught the eye of a gangster on the suburban railway.

Xu Mo, a modern high school student was sent back in time to Jing Kingdom and found herself trapped inside of the body of a princess with the same name.

She had barely recovered when she learned of an unparalleled fiancé and in a daze, they got married. Then the stunning genius physician who normally does not pay attention clamoured to marry her. After that, there was a cold general, a flirtatious lord, a tsundere young master……

As it turns out, this was a male-dominated dynasty. Because the female population was sparse, the entire nation shared wives regardless of rank or nobility. Is it feasible for someone who wants to maintain monogamy in this dynasty?

- Description from Novelupdates