Controversy over obsessed fans is firing up again after a netizen posted an online ad Monday, advertising a pair of underwear for sale, supposedly belonging to D.O., a member of K-pop group EXO.

On Jan. 20, a photo of men’s underwear was posted on social network service Kakao Story with the caption, “Do Gyung-soo’s (D.O.) underwear for sale.”

The poster, who is believed to be a “sasaeng fan,” offered to sell the underwear for 100,000 won ($94), writing that she had taken the item from his dorm herself and it was extremely difficult to get.

“Sasaeng fan” is a Korean term combining the word “sasenghwal” (meaning privacy) and fan, which refers to obsessed fans that follow their favorite stars almost around the clock. Their clingy behavior has posed a threat to the safety and privacy of Korean stars.

“Can’t you believe it is really his? A few hairs remain on his underwear, so ask for a DNA test. Don’t complain about it,” the netizen said in the comment.

EXO, a K-pop idol rookie group, has suffered from a series of problems regarding obsessive fans. Previously, a group of fans came under fire for crashing the wedding of member Baekhyun’s brother, as well as launching an online petition to exempt EXO from mandatory military service.

By Ock Hyun-ju, Intern reporter (laeticia.ock@heraldcorp.com)