And now, the accusation from one supposedly scorned ex-girlfriend seems set to shock the K-pop world.
It was reported that in a post published within an online community, a netizen accused EXO's Park Chanyeol of cheating while the duo were dating.
The netizen claimed to be the 27-year-old idol's ex-girlfriend and that she had discovered the sordid truth just before their third anniversary.
And it wasn't just that Chanyeol was allegedly two-timing her; she also claimed that he cheated on her with more than 10 women, and they included "girl group members, YouTubers, broadcast DJs, dancers, stewardesses, and more".
According to Koreaboo, she wrote: "Recently, [as we] approached our third anniversary, I found out a shocking truth. I tried not to believe it until I personally saw and heard it for myself, and I believed you when you said it wasn't true.
"But during the three years that we were dating, you became someone's first and someone's one-night stand. While I was sleeping peacefully, you were always busy playing around with a new woman."
She also said: "Everyone around you, except for me, knew how dirty you are. Really, only your fans and I didn't know."
The ex-girlfriend claimed that when she confronted the singer two days after they had broken up, he "couldn't say a word and pretended you didn't know".
She added: "The funniest thing is that whenever I mentioned the names of one of the girls you played, ate, and slept with, you didn't deny knowing them. You should have at least pretended. How funny I must have been to you."
In order to protect the singer and his career, she claimed she kept their relationship a secret by hiding the photos they took together and telling even her closest friends that she was single.
"I was busy protecting you because I trusted you when you said you would kill yourself if a problem arose in your music career due to women troubles."
The post was also accompanied by shots of the singer with a companion who has been digitally edited out of the photo — presumably the ex-girlfriend who is making these claims.
In one photograph, there was a cake bearing a sign that reads "In love for 790 days" and also a man (whose face is half-obscured) wearing a grey beanie that other netizens said looks like one of Chanyeol's favourites.
According to other speculations, the interior design of the apartment the couple is shown in also matches the interior of Chanyeol's apartment as seen in a previous Instagram post by his sister.
However, a quick search of her Instagram account revealed that the photo has seemingly been taken down.
In response to the allegations, Chanyeol's management agency SM Entertainment confirmed that they won't be making any official statement.