Similar personalities don't match well as couples, though. You need someone different to spice up your life, so to speak.
I like how Rio and Yugami both turn to Chihiro.
I wonder, if by gaining a friend, did Rio go waaay ahead of Yugami in that instance? (Yugami was boasting how he is ahead of Rio). By not realising true friendships while Rio does, i think she is ahead of Yugami in that regard.