The Yuuzhan Vong, a sentient species, employed creatures known as Korsks for the purpose of scrubbing. Before the Yuuzhan Vong War, when the Yuuzhan Vong shaper Nen Yim was still a child, before the extragalactic Yuuzhan Vong invaded a galaxy different from their own, she, along with her crèche-mates P'loh and Zhul, placed a korsk in a shared dining space; the korsk then consumed all of the i'fii foodstuff present. Later, in 29 ABY during the conflict, Yim learned that the Jedi Knight Tahiri Veila possessed her memories, including the aforementioned korsk event. This discovery caused Yim to understand that her own persona had been inserted into Veila's consciousness during an effort to convince Veila of her Yuuzhan Vong identity via shaping, a Yuuzhan Vong method of bioengineering.
Greg Keyes' novel, The Final Prophecy, which was released in September of 2003 as a component of The New Jedi Order novel series, contained the sole mention of Korsks.