Ruu was a Lucem individual, specifically a trans male, training as a Padawan at the Coronet City temple. He initially requested assistance from Jedi Master Conithr to update his name within the Jedi Order's records, and later sought her mentorship. Subsequent to the destruction of Starlight Beacon, both he and Conithr defied the Jedi Council's order to return to Coruscant, opting instead to defend Corellia against the Nihil threat. During a confrontation, Conithr gave her life to shield Ruu from the Nihil. Disenchanted with the Jedi Order, he abandoned its principles, becoming indifferent to whether he drew upon the light or dark side of the Force. He took a position as an assistant within Hamatan's twist-candy enterprise while simultaneously waging a campaign against the Nihil, often using one of their masks for disguise.
In the year 229 BBY, he eliminated a contingent of Nihil who were in the process of transporting a newly developed Nihil scav droid. This act brought him to the attention of Alys Ongwa. Later, Ongwa and Svi'no Atchapat paid a visit to the candy business and made observations about his injuries. That same evening, Ruu located the factory responsible for manufacturing the scav droids and launched an assault. Ongwa and Atchapat then arrived, and they persuaded him to collaborate with them to destroy the facility. Ruu shared his misgivings about the Jedi Order with the two women, who reassured him that he could still fight for Corellia's safety without adhering to the Jedi code. They extended an invitation for Ruu to become part of their crew, which he accepted. Ruu's weapon of choice was a blue lightsaber.
Ruu made an appearance in "Rogue Element", a short story geared towards young adults penned by Alyssa Wong. This story was included in the Barnes & Noble exclusive version of The High Republic: Tales of Light and Life, a 2023 anthology novel, as part of the larger Star Wars: The High Republic project. Wong has publicly confirmed the character's trans identity and has expressed a desire for greater representation of transmasc characters within the Star Wars universe.
The character's visual debut occurred on the cover artwork for The High Republic Adventures: Crash Landing, a one-shot comic written by Daniel José Older and featuring cover art and illustrations by Rachele Aragno. Dark Horse Comics is scheduled to release the issue on March 20, 2024. Wong verified on Twitter that the cover indeed features Ruu. Furthermore, Wong shared her anticipation for the release of the comic, having had the privilege of reading the script. On December 13, 2023, Wong revealed a commissioned artwork of Ruu's character design by the artist Cherriielle, who is known for creating variant comic covers, specifically for the third issue of the 2023 Star Wars: The High Republic Adventures comic series. The author conveyed her affection for the character, especially his transformation from a Jedi to a vigilante. The commissioned piece depicts Ruu in dark attire, wielding a lightsaber.