In Ep. 11 of the 2nd TV series, Ryo-Ohki meets up 
with another cabbit named Yu-Ohki that was 
created by Yugi.  After Ryoko & Ayeka broke a 
statue, Sasami blamed it on Ryo-Ohki.  In an 
attempt to split Ryo-Ohki from the gang, Yugi 
created Yu-Ohki and lured Ryo-Ohki to the moon.  
(Not too bad of a synopsis from skimming through 
a DVD, heh.)  Later.