Writing Story improvement

[Venusaur26]

I am reading this extremely dark romance fantasy novel, but spoilers told me that many of its twists are either too WTF or too lame: https://www.novelupdates.com/series/my-body-has-been-possessed-by-someone/

If anyone here has finished it or something, can tell me how this can be improved while remaining extremely dark?

 

[RobBanks]

Consistency is key.
Also not writing twists just for the sake of having twists in there. If there's nothing to twist to begin with, then you're just twisting empty air.