In ep. 23 'Hot Springs Planet Tenrei', the following characters appear: Urt, Ark, and Handull. If you had been a fan of the Future Retro Hero Story Mangas by Takehiko Ito, you would have know that those three head priests showed up often to be a pain to Juji's crew. So it makes no surprise that they show up in FRHS's spin-off series Outlaw Star. Also as they mention a red-haired hero near the end of the esp, they are referring to Juji Thomas Godah who could possibly be Gene's ancestor.
Originally due to the Adult-theme fanservice material of this episode, this was the only episode originally not directly aired on TV in the US on either Cartoon Network's Toonami or Adult Swim. However following Outlaw Star being acquired by FUNimation and the announcement of it being included in Cartoon Network's new Toonami Block, this episode would be aired for the first time in the US as part of it on February 24, 2018, but under the TV-MA rating, and with some minor censorship for certain inappropriate scenes.