Some of the worst problems Korean personalities face is sasaengs. These are fans who break the limits and want to violate their favorite celebrities' privacy.

Sasaengs can become so obsessive that they begin to perform criminal acts. Sasaengs also use illicit means to chase after their favorites.

"Pursue the celebrity's every move even if it means using illegal ways and post obtained information online."

These sasaengs can potentially cause an accident. For example, when police tries to track them down, it may cause traffic accidents. Also, when sasaengs follow celebrities and the idols try to get away from them. All these scenarios and more can cause accidents which may also be fatal.

"But fans chase after the car of the celebrity who is travelling for their next schedule. Taxis with fans are trying to catch up with the celebrity's car, while the celebrity tries to get away. This results in a car chase."

Sasaengs also go as far as sharing their idols' personal details online. One of the major reasons that they are doing this is to prove how "knowledgeable" they are as a fan.

"They get the urge to show off to others how much they know about the celebrity. But in reality, they use illegal means to pry into the privacy of the celebrity."

A psychology professor at the National University of Seoul gave her interpretation as to why sasaengs behave drastically.

"In some degree, they are affected by the Idol syndrome. They try to show they are more exceptional than other fans, regardless if it torments the celebrities."

Another criminal practice linked to sasaengs is breaking into the residences of idols. Even with security personnel in place, sasaengs always figure out some way to get in.

"Fans pass here to get into the parking lot. Securities see them from the CCTV, but sometimes they go in a while the securities are looking away."

A defense attorney also states that many of the things sasaengs do are unconstitutional, and the law will prosecute them very harshly.

"Those actions by sasaengs fans can be legally punished. According to the criminal law, housebreaking and indecent assault can be charged on them. They can be sentenced to a maximum of ten years behind bars."

A regular fan also provided her viewpoint on sasaengs. She cited that one of the factors that they behave this way is that they choose to believe that they are different from other fans.

"Sasaeng fans are usually young. They believe they are different from other fans. They have the illusion that they actually know the members. Although we should be the same fans, they believed they are special, and they really get obsessed with mobile phones."

Sasaengs often love taking personally identifiable information concerning the idols, such as receiving Identification cards or personal possessions.

"They not only find out telephone numbers but also collect the ID cards of idols and personal belongings."

Sasaengs may also recruit people to be doing some crazy tasks for them, for example, robbing underwear from their favourite celebrity.

"A young student even said she would give 100 million won if I can get a certain celebrity's underwear."

WATCH THE FULL VIDEO OF HOW SASAENGS GO FAR FROM BEING A NORMAL FAN BELOW!