Baka to Test to Shoukanjuu‎ - Volume 12, The Eighteenth Question

Haruto Hayase was a normal high school boy in his third year, living a quiet life until his younger sister, Haruka Hayase, joined the same school. Haruka’s beauty and charm made her the center of attention, quickly becoming the school’s prima donna. But when a notorious gang leader set his sights on her, he did everything in his power to protect her—only to fail tragically. Haruka was brutally assaulted and tortured, and Haruto himself suffered an agonizing death. However, in a twist of fate, Haruto is given a second chance, waking up a year before the events that shattered his life. Armed with the mysterious ‘Debauchery System Slave’, he vows to exact revenge on those responsible. This time, he will use his newfound powers of the system and charm to seduce the loved ones of his enemies. From their mothers, sisters, and lovers to their closest friends, Haruto will make them his. His enemies will suffer as he steals what they hold dearest, ensuring their downfall in the most devastating way possible.

Ye Chu is a miserable supporting character from a novel (she transmigrated).

She’s the most famous socialite in Shanghai, but her existence was to emphasize the magnificence of the white lotus female lead.

In the previous life, Ye Chu died in an accident. After rebirth (still in the novel), she didn’t only want to get revenge, but also change her fate, allowing every side character to have the opportunity to shine. Ye Chu and Lu Huai are a fake couple in their previous lives but reunited in this life.

They probed each other at every turn and slowly got closer to each other. They two fell for each other and confronted their enemies together.

- Description from Novelupdates

Wen Xuxu is a tenacious, talented, smart and brave woman who was fostered by the Yan family at the age of four when she lost both her parents.

Although Leng Ruoxue is born mentally challenged, she is the most beloved granddaughter of the number one general in the Eastern Lake Nation. She is despised by her fiancé and schemed against by her love rival. However, she is reborn as a powerful soul. This is a fantasy world, and also a world where the strong are respected. Cultivation, alchemy, weapon refinement, beast taming—the once foolish young miss has transformed into a stunning genius. Pill refinement and weapon refinement are all child's play. Heaven Grade medicinal pill? Even my pets won't turn an eye to it. Heavenly Treasure? I have the space to grow my own. Sacred artifact? Sorry, that's too low a level. I only know how to refine divine artifacts. Beast taming? My beasts deliver themselves to my doorstep.