Great premise, less-than-stellar execution.
The art's fine, but the lack of character direction really took away from my enjoyment. Other comments say that Alisa is a strong heroine, but she wavers between ditz and insanity for me (there's nothing wrong with that, but Seol Hui lacks precision in her personality), and seems rather broken overall. The impassioned statements she makes when she shows her darker side are repetitive and self-righteous. They lack power and fall flat.
The supporting characters are also simple. Marcus has simple thoughts, despite being a celebrity. The villain is not worthy of even being called a villain- she's not crafty, just transparent.
The pacing, too, was awkward, as it drifts from event to event. There's definitely a lot of mystery there, but that's not necessarily intrigue.
If you're not a stickler for consistency, I would definitely recommend this manhwa, though.