1. She's literally asking for it. Isn't it kind of a jerk move to not give her what she wants? (I actually agree with you here).
2. You're being duplicitous, and it moves you toward Mischievous. I think that makes sense.
3. You're subjecting sapients to unwanted experimentation with permanent side-effects. In this universe, the effects aren't that bad, overall, but it's still not a nice thing to do.