You can see the outlines of Tres Magia on page 23 when they're talking about how emotions are the source of their powers.
I think it goes a bit more than that too, their powers (at least initially) are based on their deepest desires. Kiwi wanted to destroy the magical girls so everyone would pay attention to her so she got explosives, Korisu is a kid and wants to play so she controls dolls and a doll house. Korisu also seemingly wants to be in a parental or motherly role as she has taken that roll or something similar multiple times in the dollhouse which likely stems from her desire to have her mother around instead of at work.
Honestly it impresses me that a series that many would just write off as ecchi garbage actually has deep character motivations and development, for the most part at least.