In novels, there are characters called villains. They are heartless and cruel, cold and ruthless, spurn sincere feelings, and stop at nothing to achieve their goals, even if it means betraying those around them.
There are people in this world called hopeless romantics. Their feelings are all that matter to them. They spend most of every day thinking about how to maintain their relationship. Losing their beloved is like losing the whole world, leaving them unable to find a reason to go on living.
The hopeless romantics before they transmigrated: I could never be like that.
The hopeless romantics after they transmigrated: Only death can part us.
[A hopeless romantic can endure being ignored, admit their own foolishness, and even tolerate being used for the sake of that one special person. But they can never accept emotional betrayal.]
In short, this is a story about a scumbag villain betraying a hopeless romantic, only to be punished by them in return.
Theme: Love has immense power