The songs are Unknown Planet and Dear My Crazy Soulmate. The agency said both are also intended for her sixth studio album, whose release had previously been delayed because of health concerns.
The Dear My Crazy Soulmate video was scheduled to accompany the single, featuring IU as a police officer. A video for Unknown Planet was planned to follow later.
Yonhap published the report before the announced release time, so it describes the agency's schedule. The project follows Bye, Summer, released on September 10, 2025.