Hobi Hobi no Mi

The Hobi Hobi no Mi is a Paramecia-class Devil Fruit that allows the user to transform living people into toys, and erase memories of their existence from others. It has a secondary side effect of granting the eater eternal youth. It was eaten by Sugar.

Strengths and Weaknesses
The main strength of this fruit's power is that it allows the user to transform people into toys by touching them, whose memories of existence will also be erased from those who once knew them. The toys sometimes will lose memory of their own individuality as well, but other times will maintain it, along with their free will.

Another effect of this fruit, seemingly unrelated to the first, is that it halts the user's aging process upon consumption, effectively granting eternal youth.

Knocking the user unconscious will cancel out all the transformation and memory modification effects. Also, as the aging process stops the moment the fruit is consumed, the user's age at the moment of consumption may be taken into consideration of the rest of their lives, seen when the current user, Sugar, is in the form of a little girl who needs others to protect her. The user is also susceptible to the standard Devil Fruit weaknesses.

Usage
Sugar uses her powers to transform the citizens of Dressrosa and losers of the Corrida Colosseum into toys, forcing them to serve as slave labor for the Donquixote Pirates' underground trades. She also gained eternal youth, not having aged for at least ten years, since she first arrived to Dressrosa.

Trivia

 * This Devil Fruit is so far the only known to grant two, albeit completely unrelated abilities: the ability to transform people into toys, and halting the aging process.