Toaru Majutsu no Index - Volume 14, Chapter 3: Something Far Removed from Magicians. Power_Instigation.

Chen Ye transmigrates over and unexpectedly became a figure in a dark Xianxia game.He is a mere Medicinal Farmer, yet he has two disciples, who will be two legendary Fairies.The first disciple, Lu Zhiwei, is the foremost Righteous Fairy in the world.The second disciple, Xu Qingjun, is an evil-doing demon path enchantress.However, looking at the two shivering little girls curled up into a ball, Chen Ye realizes that he transmigrates five hundred years earlier.And unfortunately, the former owner of the body seems a harsh master to them so that the tea served by Xu has been poisoned.“This tea...”“It's too bitter, I won't drink it.”

Twenty-six years, Jiang Yun experienced three things:
girlfriend Qin Zhao cheated;
quit his job;
Another new love.

【You are the fireworks of the world and boundless obsession】

Demining:
1. Do it first and then love the text. Jiang Yun and Lu Nian didn’t care about it in the early stage (emphasis added), so why not talk about feelings, and Lu Nianzhi and Qin Zhao are friends. That is, Qin Zhao cheated, Jiang Yun found another new love (who had broken up), and Lu Nianzhi was digging.
2. The clean party is careful to enter, Jiang Yun has an ex-girlfriend.
3. The broken mirror does not reunite, and Lu Nianzhi’s he, abusive scum text.

Content tags: Encounter by fate Near water towers Heaven made synthetic growth
Search keywords: Protagonist: Jiang Yun, Lu Nianzhi ┃ Supporting role: Qin Zhao ┃ Others:
One-sentence introduction: abused scum, broken mirror will not be reunited
Purpose: Get out of frustration, keep improving, and become self-reliant

- Description from novelbuddy

Reincarnated into an eroge brimming with cunning and seductive women, Shia quickly learns this world is no paradise. His childhood friend? A manipulative beauty with a penchant for control. The maid? A silver-haired, venomous tsundere. Even the elegant motherly figures hide sharp fangs behind their kind smiles.Fortunately, Shia knows this world’s secret: a unique system that only he can use. From making alliances with snake-like in-laws to hosting wild parties in the elf kingdom, Shia takes charge as the self-proclaimed administrator of chaos. But taming bad women isn’t easy, and Shia’s life quickly turns into a whirlwind of power plays, unexpected friendships, and wild nights.

One day, Luo Jian woke up from his sleep and found himself in a locked chamber where the door and window were all sealed. A note with a few lines written on it was tacked to the wall: “Escape from this room within an hour, otherwise, you will die.”

There is a sequel called Reincarnation Night (轮回之夜) that takes place in the same universe but has different main characters

- Description from Novelupdates