Looking for this webtoon

I read this webtoon a while ago which was set in a universe where people were categorised into four types.

(sorry this is going to be long)
I don't specifically remember what the names were but they were around something like this:
1. Normal/Average: kinda like betas in omegaverse, they're just normal people.
2. Pretty/Docile: kinda like omegas in omegaverse, they're really pretty, but all of them have one special attribute/flaw: (i think) they can only fall in love with one person (kinda like their destined partner).
3. Violent/Destructive: these people are kind of rare and most people don't hear about them often. They take pleasure in killing people.
4. People who have the ability to see what category people belong in without having to conduct tests on them.

The webtoon is set in Korea.
The female lead is part of the pretty category, she has grey curly hair and lived abroad, before transferring to a school in Korea for high school to find her "destined partner". She met the male lead a long time ago in England when they were still children, but she had a very deep impression of him and was able to recognise him immediately afterwards.

The male lead is part of the violent category. He has black hair, and wears glasses. He was initially very cold to the female lead, but because she kept pining and chasing after him, he gradually grew to like her and care for her. The female lead does not know that he is part of this category, which is why he refrains from killing people.

The climax/major event of the story was that the FL and her best friend (normal) was kidnapped. They were kidnapped by their art teacher who was good looking and popular amongst the female students, and were both knocked unconcious. The FL was nearly raped. The ML had previously installed a GPS tracker on the female lead's phone, (and for reasons I forgot) realised something was wrong and found the female lead. He murdered the art teacher and hid the body before calling the police. He gets together with the female lead not long after that.

At the end, several people close to the FL know the ML's identity as someone in the violent group, but chose not to tell her because they were scared of the ML. Her best friend tells her, and the FL reveals that she knew a long time ago but still decided to stay with the ML.