Horo Horo no Mi

The Horo Horo no Mi is a Paramecia-type Devil Fruit that allows the user to produce ghosts. "Horo" means "Hollow", referring to the user's ghost-like powers. Horo can also refer to the way Perona laughs. In the Viz Manga, it is called the Hollow-Hollow Fruit. This fruit was eaten by Perona.

The powers of the fruit were first seen being used with one of Perona's ghosts spying on the Straw Hat crew unnoticed. It was only during their dinner with Brook that they noticed it.

Strengths and Weaknesses
The major strength of the fruit firstly, as demonstrated by Perona, is that it gives its user the ability to produce spectral replicas that they can control. These replicas can come in different forms and are all immune to physical attacks. The most basic of these forms are Negative Ghosts. Should a person be passed through by one of these, they immediately fall on their knees in manner similar to Foxy and become very negative about themselves. These replicas can also be used to gather information from different areas.

Though the power of the user's Negative Ghosts are seemingly unavoidable, they have no effect on a person who is originally pessimistic about himself. This is clearly seen when several of Perona's Negative Ghosts passed through Usopp. Usopp, being pessimistic about his own abilities, was completely unaffected by them, in fact Usopp even caused the negative ability to backfire on Perona and her Negative ghosts causing them to collapse with negativity.

The user also, in order to use a more advanced form of a ghost, becomes completely limp and immobile. This is because this is a form of astral projection of their consciousness using the Devil Fruit's power. Their astral projection may be strong against physical attacks but while they are projecting their consciousness, their main body is completely susceptible to any attack.

Other than those mentioned, the user is also susceptible to standard Devil Fruit weaknesses.

Usage
The fruit's bestowed powers, as used by Perona, have been used for both combat and information gathering situations. She has used her Negative Ghosts to weaken enemies so that her allies, like Absalom's Zombie Soldiers, can have an upper advantage. She has also used her ghosts in an elaborate information gathering and surveilence system, called "Ghost Network", in order to monitor things around and on Thriller Bark.

Perona is also able to use her Devil Fruit powers to create other kinds of ghosts. One ghost she can create looks perfectly like her in every detail. This ghost is able to float in midair, go through solid objects, and change shape. This ghost is actually an astral projection of her consciousness and thus allows her to attack opponents without them attacking her directly. Perona is also able to create explosive ghosts of varying sizes which she can use against her opponents.

The named techniques that are used by Perona that involve the Devil Fruit are as follows:


 * Negative Horo (ネガティブ・ホロウ, Negative Hollow): Perona sends out multiple ghosts to drain the will of a foe, either on one person or many.


 * Yonbai no Negative Kōgeki (四倍のネガティブ攻撃, Quadruple Negative Attack): Perona sends four ghosts at four separate targets to drain their will. This is an anime only technique.


 * Mini Horo (ミニホロ, Mini Hollow): Perona creates miniature ghosts the size of her palm. With these she can send and make them explode. This was first seen being performed before Usopp.


 * Ghost Rap (ゴースト・ラップ): With the Mini Horos, Perona sends them toward an opponent and makes them explode at the snap of her fingers. This technique in which explosive ghosts are sent towards an opponent resembles the "Super Ghost Kamikaze Attack" technique of Gotenks from Dragon Ball Z. This was first seen being used against Usopp.


 * Toku Horo (得ホロ, Special Hollow): Perona creates a much bigger version of her Mini Horos and sends it after her opponent.


 * Kamikaze Rap (神風ラップ, Divine Wind Rap): Perona snaps her fingers and detonates her Toko Horo causing a massive explosion.


 * Negative Ghost (ネガティブゴースト): Said to be Perona's strongest attack, she generates three Negative Horos and a Toko Horo. We never see precisely what this attack does, as Bartholemew Kuma stops it effortlessly.

Trivia

 * One of Perona's ghosts appears behind Zoro in a panel in Episode 337; however the crew failed to notice it at the time.
 * This Devil Fruit's name is a reminiscent of Perona's signature laughter, "Horohorohoro". She shares this attribute with Edward Newgate and his Gura Gura no Mi, "Gurararara".

wherein Hollows are malevolent spirit/ghosts, but don't look anything like the ones from her Devil Fruit.
 * The name might come from a different popular manga series; 'Bleach' by Tite Kubo,