This is an ancient-style fantasy with a deranged male lead and a 1vN romance. The tags are wrong.
[Plenty of love-triangle drama + 1vN + deranged, gloomy men + everyone's favorite + frail female lead + scheming drama queen]
After choking to death while drinking water, Su Jinxue transmigrates into the body of a sickly general's legitimate daughter and is bound to a survival System. She discovers that the original owner is not only terminally ill, but also a heartbreaker.
The unreliable System, oblivious to the danger, binds her to the four men the original owner had kept around.
Xie Ciyuan, the young duke's son and her gentle, aloof childhood friend, becomes a lunatic with an overpowering need to control her.
Gu Xianzhi, the renowned general of Qi, becomes a madman who wants to die alongside Su Jinxue every day.
Qi Guan, the decisive crown prince, becomes a teary-eyed puppy who wants to cling to Su Jinxue every second.
He Chen, her personal bodyguard, turns into a gloomy man who secretly watches her every move.
Su Jinxue resolves to work hard and extend her life for as long as possible.
Xie Ciyuan: You have other men? You're so disobedient. Do I have to tie you up?
Gu Xianzhi: You lied to me. I'll die with you, then we can be together forever.
Qi Guan: I knew it. Why are you always so busy? Has anyone else been here, or do you like it when we're all together?
He Chen: Mistress, do you want all four of us to serve you together? I don't mind. Please don't leave me!
Su Jinxue: This is bad! Why is everyone so messed up?
After the System upgrades...
System: [Host, don't panic yet. There are still five, six, seven, eight... more men on their way]
It's okay, but I'm a little tired of watching it. I'm going around between several men, saying that I like whom and don't like others in front of everyone, and I'm worried that my love affair with other men will be discovered, which makes me feel tired.
It looks good, it looks good, it looks good, I like it. I finally found this type of ancient text that I like.