YSS Ouroboros, NG-X1-415, is a Plumeria-class (2D) Medium Gunship built at Gemini Star Fortress by Ketsurui Fleet Yards in YE 30 for the Star Army of Yamatai's First Expeditionary Fleet and upgraded to the 1D variant in YE 31. She is commanded by Taii Fujita Kin.
The YSS Ouroboros is part of the Seventh Squadron, under the command of Taisa Ise Katae.