f(x)'s Luna confessed she had hemorrhoids.

On the January 30 airing of MBC's 'Radio Star,' Luna revealed, "Hemorrhoids are genetic, so I get hemorrhoids often when I'm stressed." She also shared, "There were many wire scenes when filming the children's movie 'Bungaeman.' The scenes were all taken at once and I got hemorrhoids then."

Luna added, "I continued to film with a smile while suffering from hemorrhoids. I worked hard as a rookie actress." 

To Luna's honest confession, the MCs commented, "Are you allowed to talk about this? Isn't it like the first for a girl group member."