Hmm. Mysterious Lillie looks a lot like Caitlin from the Unova Elite Four. This certainly doesn’t hurt the theory about Caitlin appearing in Sun/Moon (which began based on her name appearing in the Japanese trailer and was fueled by her in-game quotes). Is Lillie her sister perhaps?
“This is my villa. I have villas all over the world”
“I used to own Battle Castles. Then I became one of Unova’s Elite Four. Will I be a Champion somewhere next? You never know!”
The elite four are often regarded as the strongest four trainers (baring the regions champion) of the region in which they reside. The only exception being Kanto and Johto who share an elite four, which has changed over the years with Bruno being the only staying member. The concept of the elite four is based on the ‘four heavenly kings’ who are gods in Buddhism.