Under Korea's criminal law, sexual violence against individuals of the same sex is classified as "quasi-rape."
According to police in Yongsan, the alleged man claims he was sexually assaulted while sleeping at the studio. He said he became aware of what had happened after waking up and reported that there were other men at the scene.
Police have not yet summoned Yoo for investigation. "We will launch a probe as soon as we obtain relevant information," they said.
The 37-year-old actor is currently undergoing court trials for taking drugs including the knockout sedative Propofol and other narcotics, more than 220 times between September 2020 and March 2022, sometimes using aliases.
Prosecutors have sought a four-year jail term for the actor, who earned fame with several hit films including action comedy "Veteran" (2015).