Interesting game, although I'd like to make some suggestions.
The girls' profiles could be completed when they level up, things like where you can find them, the type of crystal they produce, or who they have a special event.
I realized that if you have a level 2 girl in an extractor, and you bring another girl to train yourself, the attention level increases. Is this intentional or a bug?
A fourth machine could be very useful. Have 3 extractors so don't run out of crystals, and an extra one to train.