Where she stands at the Milk Farm, stand there, you need to do that first to Activate her, or she in the Forest.
well, i have activate her. before she left, if I'm not wrong, I was on the quest where i took her to places that could increase her breast size.if I remember, i only brought her to rinny places (the workshop in rinny's house) then i guess to the graveyard(to meet the master of the mansion in the graveyard after you finish rinny's quest regarding the mansion)? i don't know where she went after that.