Some sasaengs go further than that, as they keep committing more foul activities, to the extent that they are becoming popular. A channel called Kpop Stories has put together a list of several of Sasaeng's most notorious followers.

Here are four of the most disturbing K-pop sasaengs with terrible personalities:

DUCKIE CHOY

This is a sasaeng fan known for her hard-headedness. This girl from Hong Kong is constantly following NU'EST's Hwang Minhyun and posting very similar pictures of that male artist on her social media.

Duckie Choy, apart from having to follow Minhyun, also intruded into "PRODUCE 101" residence hall.

This sasaeng supporter has gone into the bedroom of the trainees, scurried through the belongings of the boys and poked fun at it on her SNS: "geez, there really is nothing tasty in it. They all brought a bunch of treats along with them. Haha!"

RION

One time, a young woman named Rion pursued and sexually harassed the leader of the EXO. This is Japanese sasaeng supporter and her nickname is Rion.

Remarkably, when she was just 16 this girl has begun her existence as a sasaeng fan but used to be Suho and Chen's masternim of "Moncheri."

Rion has always shown inordinate affection for Suho according to EXO-L.

She's decided to send him a napkin with her lipstick smudge on it, pursued him to every occasion, continuously using filthy and outrageous phrases to beg for sex with the EXO leader.

Suho also recognizes this girl's existence. Whenever this lady took her pictures, he is indeed very annoyed and always continues to refuse her presents.

LU YAO

There are numerous videos of this mad sasaeng fan named Lu Yao exhibiting acts that are inappropriate to members of the BTS.

While at the airport she attempted to speak to V and Jungkook but ended in failure to do it at all.

Each time she accompanies the boys, Lu Yao has also always managed to pick the most glamorous clothing and make-up to get the members interest and has never been successful.

ARMY said: "This woman showed on BTS flight back to Korea.

She pursued them all the time, this is becoming too much. We wish the company is going to tighten up public safety.

Don't allow that to happen anymore. This wasn't the first time she follows BTS so please include her name in the blacklist. Please respect the privacy of BTS."

Immediately after that, Big Hit responded by publishing a comprehensive list of fans barred from attending BTS' potential activities on the fan cafe of BTS.

Lu Yao is on the blacklist as per the report, since she "preceded the artists on departures from January 1, 2019 to January 14, 2019."

LCHAN

Like the above sasaeng followers, it is understood that LChan is a mad girl who chooses to follow Suga (BTS) whenever and wherever.

There's a compilation album of several close-up shots she took of the male idol on her Instagram, there's also a picture of Suga putting up his phone to alert LChan for stalking him.

Doesn't really seem to worry about the danger of the ARMYs, LChan has still not halted her existence as a sasaeng fan.

This girl posted a picture captured at the stadium on 17 June, where BTS is practising for the "BTS MUSTER" before the series.

No one knows how LChan reached the area when the event had not yet begun.