He pretended to be his girlfriend for weeks after he killed her.

A tragic murder with a perverse twist.

Trigger warning: This post contains details of intimate partner violence and murder.

Sunny Kim was murdered on the 2nd of May, 2015.

She was brutally beaten to death by her abusive boyfriend after attempting to break up with him.

But, no one knew that 26-year-old Sunny was even missing until two weeks after her death.

In that time, her boyfriend — known only as Mr Lee — continued to impersonate Sunny by using her Facebook and email to stay in touch with her family and friends.

“The last message I sent her asked, ‘Hey, how are you?’ I later found out I didn’t hear back because that was the night she was murdered,” one friend told Buzzfeed News.

On the day she was murdered, Sunny Kim had accepted a new job. She rejoiced with family, friends and her boyfriend.

But on the same day Mr Lee emailed that employer — posing as his girlfriend — to explain she had decided to turn down the job offer and return to the United States where she had previously studied since she was 14.

Over the next two weeks, Mr Lee also responded to text messages from Sunny’s family — impersonating his girlfriend’s exact tone and character to cover his tracks.

“The way that he text me was how my sister would text,” Kim’s sister, told BuzzFeed News. “We think he may have gone through her phone to see how she usually contacts us. It was really shocking to see how someone can really hide what they did in that way.”

According to Sunny’s friends, she was a popular and kind-hearted girl whom everyone adored.

“She loved to cook, clean, do arts and crafts, play video games, watch movies, and sing. She always said she rather spend her money on a good meal she can have with her loved ones than on materialistic things,” one friend told Buzzfeed.

“She was able to turn life’s smallest moments into wonderful experiences and memories and share it with the people close to her,” another said.

But her boyfriend was known to be abusive. He frequently stalked and hit her.

“I heard from close friends of hers there that one time my sister kneeled and begged for him to stop beating her,” her sister told Buzzfeed. “I think she thought he had changed, and they dated again — it probably happened over and over again.”

Last year, photos of Sunny’s injuries — bruises, black eyes, broken bones — were shown to police. But nothing was done.

After his two-week charade, Mr Lee turned himself into police.

He admitted to killing his girlfriend and said he had attempted to take his own life.

He told them he beat his girlfriend out of anger that she was breaking up with him. The police later found footage of him following her home, before entering her house to kill her.

He stuffed her lifeless body in a suitcase, carry it up a mountain and bury it — covering the hole with cement, dirt and freshly-planted flowers.

Ms Kim’s autopsy results are yet to be released, but authorities described the body as “badly damaged.”

Buzzfeed reports a video was released of Ms Kim’s mother confronting Mr Lee at the police station.

“As long as I live, I will never forgive you. You don’t even deserve to be judged by law. You’re not even a human being,” she reportedly said.

“She had told me that she finally got a great job back in Korea, and everyone was dying to see her. I never imagined I would see her body like this.”

Ms Kim’s friends and family are devastated at the loss of their loved one.

“My family is completely broken. We are all shattered into pieces. My mum and my grandma have had a total breakdown. My mum can’t sleep, and my dad has been giving her pills to help her sleep — she’s been awake all night crying,” her sister said.

“I can’t focus on what I am meant to be doing, I’ve been crying so many days and nights. Right now we feel like no one is with us, our country, our law. Who’s with us?”

Do you have a news tip? Email us at news@mamamia.com.au.

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