Would you be able to recover from the traumatic experience of being raped by Nico Robin? Think about it, her Devil Fruit makes raping you an effortless endeavor. She can hold you down with any number of sprouted arms and force you into any position she wants against your will. No matter how badly you struggle, you aren't getting free. She can force you to kiss her, force you to impregnate her against your wishes for as long as you want. There's nothing scarier than being powerless and at someone else's mercy. You could get mentally broken or scarred for life if she did that to you.