Born on September 26, 2000, Olivia Marsh (올리비아 마쉬), also known by her Korean name GYUNA (규나), is a South Korean-Australian singer-songwriter under MPLIFY. She is also the older sister of Danielle Marsh from NewJeans.

On March 31, 2024, Olivia released “LAVA,” her first song as a singer, which is part of the soundtrack for the JTBC drama Hide.

On September 13, 2024, Warner Music Korea announced that Olivia had signed on with its newly established subsidiary, MPLIFY, and will make her solo debut sometime in October.

Almost a month later on October 9, 2024, it was announced that Olivia would debut on October 16, 2024, with the single “42.”

On February 13, 2025, Olivia released her debut studio EP, Meanwhile.