Sorry. Lots of posts since I started typing this one, including some that revealed that the Druid is both male and a character the PCs have been introduced to by reputation: my druid below wouldn't work so well, but I'll leave her anyway in case anyone else likes the idea.
Nothing says the druid's evil needs to be related to their connection to nature. Reading the title of the thread, what sprang to mind was a female druid who runs a forest-dwelling "orphanage" of sorts, near a city, for children that run away and end up there, and children whose parents die and they wander to there. Sometimes the druid sees children with their parents in caravans or such who "didn't look happy where they were," and takes them - and sometimes in the process of raiding caravans for supplies and killing all the adults, she ends up with some leftover children. Some of the older children have eventually taken to her ways, as well, stealing what they need and taking the occasional child as well. The younger children are made to understand that the welfare of the other children is based on their "good behavior", frequently with violent demonstrations.
Plot hooks leading to this character could be looking for a missing child, investigating a series of petty thefts in the city with similar MOs, checking into a missing caravan with evidence of missing children in the wreckage site, or one of the PCs noticing a young teen who looks to have been violently abused and following up on it.
And thus the druid's Evil has nothing directly to do with her connection to nature - nurturing plants might be the thing she does where she
appears the most Good.
And of course, all this is leading up to the scene with a young girl who has only recently been allowed to go back into town with the older children to commit some of the thefts, who brought back a fencing foil, nuch to her mistress's displeasure - "No....METAL.....
WEAPONS!", thrash thrash thrash.
