The Soru Soru no Mi is a Paramecia-type Devil Fruit that allows the user to freely interact with and manipulate souls. It was eaten by Carmel, but the ability was later transferred to the Yonko Charlotte Linlin, after Carmel's death.
- "Soru" comes from Souru (ソウル?), the Japanese pronunciation of "soul".
- In the English dub, it is called the Soul-Soul Fruit.
Strengths and Weaknesses
The fruit's power of soul manipulation, as demonstrated by Big Mom, consists of drawing out and manifesting fragments of humans' souls into a spectral, light-colored, but (for the user) tangible substance, which the user extracts by grabbing at the substance when it begins surrounding the body and pulling it out. This effectively steals from a target's very lifespan, the amount of which being determined by the user, shown to be up to and possibly beyond decades at once and down to the second if desired. Thus, if they lose too many years at once, victims may be killed instantaneously. However, the extraction process does not seem to be painful to its victims.
By infusing objects and living animals with soul fragments, the user can "humanize" them. Recipients (which Big Mom refers to as "Homies") develop human-like intelligence, with inanimate objects gaining a life of their own in the first place, and undergo transformations to more closely resemble humans. Though the only prominent change in objects are their human faces, animals will more so have their general physique affected to varying degrees, such as becoming able to stand up-right. If a Vivre Card is infused with a soul fragment, instead of becoming anthropomorphic, the card will exude a bright aura that only Homies can see.
In addition to stealing and using the souls of other people, the user may manifest their own soul into living fragments (which Big Mom refers to as Incarnations) in the form of roughly human-sized, dark, somewhat humanoid blobs, which possess limited sentience and can absorb people's souls as well.
Soul fragments extracted from one's lifespan cannot be infused into other humans or on corpses. Furthermore, the target of the soul extraction must be at least somewhat afraid of the user or afraid of death itself in order for the user to take their lifespan; if the target is not afraid of Big Mom or death in the slightest, her powers will have no effect on them. Similarly, if Homies experience extreme fear, they instantly die and wither away. Homies cannot attack anything infused with the user's soul, such as the user's Vivre Card, even if such an object is in the hands of an enemy. Homies created from others' souls are also weak to the powers of the Yomi Yomi no Mi and will faint against its user if they exude the energies from their own soul, although Homies created from the user's very own soul are immune to this. Homies are also susceptible to physical pain and can be injured or even killed with a lethal enough move, their faces suggested to be their most vulnerable spots. Prime examples include: King Baum, who was killed after being vertically bisected by Amande; a door Homie whose face was carved out; Prometheus, who was wounded by Brook (despite its elemental composition). While the Homies are typically subservient to the user and will not ordinarily defy them, they do possess their own minds and can turn against their creator if motivated enough, even going so far as to harm other Homies. 
Other than these things, the user experiences the standard Devil Fruit weaknesses to water and Seastone.
Carmel has used the fruit's power to manifest a fragment of her own soul to create Homies. By applying this to flames, she was able to suppress its destruction and compress it into a sentient form, and making the denizens of Elbaf believe that she summoned the sun god.
- Geburtstag (ゲブーアツターク Gebūatsutāku?, literally meaning "Birthday"): Carmel manifests a piece of her soul from the palm of her hand and infuses it into an object or animal, turning it into a homie. She was first seen using this technique to create Pandora. Geburtstag is the German word for "birthday".
Big Mom has imposed a toll on all citizens of Totto Land, forcing them to give up a month's worth of their soul and lifetime every six months or leave. Those soul fragments are collected by her Incarnations and sprinkled all over the islands of Totto Land, where they settle into random objects or animals to turn them into Homies. She has also used the power to kill people by taking a lethal amount of lifespan from them.
She has also created three special Homies out of pieces of her own soul; these Homies are more powerful than regular ones, and as such are resistant to the powers of the Yomi Yomi no Mi. These specials homies are Napoleon the bicorne, Prometheus the sun and Zeus the thundercloud. The latter two can be used to produce massive amounts of fire or electricity, somewhat mimicking the abilities of the Mera Mera no Mi and the Goro Goro no Mi, and can also combine their powers to create storms, granting Big Mom control over the weather. On the other hand Napoleon is a sentient bicorne that Big Mom wears for the entire day and can receive signals from other Homies all over Whole Cake Chateau, sensing any intruders and relaying the information to Big Mom. Napoleon can also reveal a blade and handle to become a sword for combat.
- Incarnations (化身 Keshin?): The Incarnations are large, black, humanoid blobs who collect the Totto Land residents' biannual payment of a month's worth of their lifespan. They are made from pieces of Big Mom's own extremely powerful soul, and are themselves capable of extracting other people's souls, via Soul Pocus. They are intelligent enough to be capable of human speech and understand basic orders. They are voiced by Masaya Takatsuka in the anime.
- Homies: The Homies are the result of infusing the collected soul portions into animals and objects, who are subsequently anthropomorphized. The fragments cannot revive dead humans or enter living ones. Also, they are unable to approach something infused with Big Mom's own soul, the incredible presence and power of which only they can sense. Finally, they are weak against the power of the Yomi Yomi no Mi.
- Soul Pocus (魂への言葉 (ソウル・ポーカス) Souru Pōkasu?, Literally "Words to the Soul"): Big Mom speaks directly to the human soul's attachment to life, while striking fear into her opponent. She will demand that the person either give her what she desires, or give her their lifespan. If the person fears death for even a moment, Big Mom will be able to take their lifespan in any amount that she chooses; she can even take a person's entire remaining lifespan, instantly killing them. However, if the person is completely fearless when they choose to have their lifespan taken, Big Mom will be unable to do so, nullifying the technique. It was first seen used against Charlotte Moscato, and was later named by Morgans when Big Mom used it on her cooks. The Incarnations are capable of using a lesser version of this technique, where they take a month of every Totto Land citizen's lifespan if they wish to stay in Totto Land. Unlike Big Mom's other usages, the people will have their lifespans removed if they choose to do so; it is unknown if fear plays a role in this.
- Heavenly Feuer (天上の火 (ヘブンリーフォイアー) Hebunrī Foiā?): Big Mom grabs Prometheus and throws it at her target, creating a large, fiery explosion. It is powerful enough to hurt someone who is using a fire-resistant Raid Suit. It was first used during her rampage in Sweet City, but was only named when used against the Sanji Retrieval Team. Feuer is the German word for "fire".
- Raitei (雷霆 Raitei?, literally meaning "Thunderbolt"): Big Mom summons Zeus around her left hand and then slams it down on her opponent, striking them with a massive bolt of lightning. It was first used against Vinsmoke Judge, and was powerful enough to knock him out.
At some point, Carmel consumed the fruit and used it in deceiving the giants of Elbaf. When she died, her powers were somehow transferred to Charlotte Linlin who would have the power for sixty three years and used it to create her dream country.
- This fruit's power resembles that of the Kage Kage no Mi, as it can take a normally intangible part of a person (in this case, souls instead of shadows) and insert it into something else, which becomes animated, and that when the said part is taken, it becomes detrimental for the owner.
- Similar to the Kage Kage no Mi technique Doppleman, the user of this fruit is able to project part of himself that share some of their abilities, called Incarnations.
- One of the major differences between the two is that while a Kage Kage no Mi user takes the shadows of humans and can insert them into any other form of life, even other humans and corpses, a user of the Soru Soru no Mi cannot insert the soul fragments into another human or a corpse.
- Another difference is that the shadows taken by the Kage Kage no Mi will disappear when the original host will die, while the Soru Soru no Mi can take the entire lifespan of the target and its soul is still usable.
- Furthermore, while a reanimated corpse through the Kage Kage no Mi uses the entire shadow of the victim (therefore, making the victim shadowless), a homie requires a very small piece of a soul, equivalent of a month of one's lifespan.
- Zombies created by the Kage Kage no Mi have their wills bound to the user's and will absolutely obey, while homies created by the Soru Soru no Mi have their free will and can, with sufficient motivations, defy the user's orders.
- This fruit's power also resembles that of the Mero Mero no Mi, as it requires the target to feel a certain emotion towards the user for their powers to work on them (fear and lust, respectively).
- Big Mom mentions that lifespan is her favorite food, implying she can eat the life she takes. However it is currently unknown if this gives her any benefit other than flavor.
- This fruit is the second one to display soul-related powers, the first one being the Yomi Yomi no Mi.
- All three special Homies (Zeus, Prometheus, and Napoleon) share the same voice actor.
- Big Mom's Soul Pocus may be based off the practice of trick-or-treating.
- Soul - Wikipedia article on the concept of a soul
- Life Expectancy - Wikipedia article about life spans