In both pretty sammy series, Ramia is Tsunami's 
rival candidate to be queen and Rumia is her 
little brother.  In the TV series, there is also 
a third candidate named Romio (Ayeka's cameo 
appearance; there is actually a different Romio 
in the first ep but that's a gaffe in the 
storyline that's [not] explained in a few seconds 
in one of the later eps).