I was thinking perhaps someone who could effect people in their dreams, an art student trapped by other expectations and desired from her that she craved escaping in her dreams. It only works if she’s had physical contact with them and can find them in the dreamscape, but the longer she used it and the longer she dream the more reality starts to fade and she has a harder time deciphering whether she’s awake or dreaming. 

I can expand on that more if you want, it’s just a general concept.