merely a misinterpretation on Leo's part. Mansherry is truthfully benevolent and kindhearted, as shown when she realized she had been tricked by Doflamingo and refused to heal the injured officers of his crew, knowing they would just keep hurting people and exploiting the dwarves of her kingdom. As a dwarf, she is incredibly fast and much stronger than her size would suggest. Her speed seems to be high, Mansherry ate the Chiyu Chiyu no Mi, the ability to instantly heal any living being's injury.