Yuna of the group AOA released the KBS2 series "Woman of 9.9 Billion."

Yuna participated as the sixth OST singer of ‘Woman of 9.9 Billion’. The song "My Diamond" sung by Yuna was released on major music sites at 6 p.m. on Jan. 9.

"My Diamond" is a song that reveals the ambition and aspirations of a woman with a diamond in her hand, which everyone wants, and expresses the desire and change of the character, which is delicate and strong. In particular, a solid drum rhythm and intense rock style guitar sound, along with the charming voice of AOA Yuna, will enrich the drama’s dramatic atmosphere.

Yuna, the main vocalist of the group AOA, recently completed her successful music career with the title track "Come See Me," and has been receiving OST love calls from various dramas to show off her outstanding vocal skills.

Woman of 9.9 Billion is a drama about a woman who happens to have 9.9 billion won in cash and fights against the world, which airs every Thursday at 10 p.m. Meanwhile, "Woman of 9.9 Billion" OST Part.6 "My Diamond" will be released at 6 p.m. on Tuesday.