I honestly hope that Royal-chan/Ribbon-chan/Princess/(Maybe?)P5MC is actually just a rival to the Phantom Thieves, not like she's a rival in Mementos, but as in she's like Goro and she brings a new opinion to the table mainly because she does bring up a good point. And, weither or not she is a part of the Phantom Thieves doesn't matter to me all that much. Because I think this gives Atlus the potential to show us other opinions in Persona 5. I know that this is a teaser trailer, but I honestly hope to goodness that she can bring more diverse characters opinions to the table, as in the game all we've seen is "Yes, I like them," or "No, I don't". And, I'm hoping with this character we get more opinions that aren't as simple as yes or no and hopefully one that's even a "I don't know" or "maybe, maybe not. I haven't met them. So I can't tell you."