Vinegar Doppio

Vinegar Doppio (ヴィネガー・ドッピオ) is Diavolo's younger, more innocent and eccentric underboss. As a member of Passione, he thinks of himself as the most loyal subordinate to Diavolo.

Appearance
Doppio appears as a fairly slim and muscular young boy with a neck-length ponytail, tied back with either a complicated weave-like braid or a hair clip. The front is left loose and sweeps over to one side, but the side flips often, and the length isn't consistent. He also appears to have freckles and pink irises that disappear when he is not in control of the body; however, like Diavolo, if he has his eye highlights they tend to be triangular. His clothing consists of a light-colored sweater with gash-like openings on it that ends right above the midriff and purple jeans with studs openings on the thighs and ankle sides. Presumably he wears Diavolo's black mesh shirt underneath, though it is much longer than the sweater itself and is not seen through the holes (or at all) until the sweater is removed.

Personality
"I didn't have to predict that... I guessed correctly...Buccellati won't sacrifice a kid like me..."

- Vinegar Doppio

Doppio is more of a regular kid: friendly, honest, and a bit cowardly. Doppio regularly hallucinates random objects as "phones" with which he talks with his alter-ego, not knowing that they share the same body.

Doppio mostly behave like a good-natured teenager, and is by default a friendly and polite individual. Doppio seems good with children here and there as he once successfully borrowed a toy phone from a child while taking a train and risked his life to save another one. Whenever attacked, automatically Doppio reverts to a state of true fear and submission, often choosing the safest option such as comply with his aggressor's demands. He believes himself to be unlucky, which provides an ironic contrast to Diavolo's good fortune.

Fiercely loyal to his boss to a point of attempting to fulfill the mission first and foremost, Doppio is smart and quite resourceful, even if Diavolo has to counsel him from time to time. Despite this, though, bits of Diavolo are in Doppio: during the battle with Risotto Nero, Doppio refused to leave the battle or have his boss step in, remaining and doing all he could to find weakness in Metallica.

As Diavolo is very gentle and patient with Doppio, he is usually completely unquestioning, agreeing to whatever his "boss" says. As he dies, Doppio's last thoughts are of his boss. He remains faithful until the end and smiles, saying that if Diavolo is going with them he'll surely win and asks Diavolo to call him, remarking that he feels lonely.

He shares his alter ego's collected nature when in battle, and while his first actions are usually panic and screaming he soon and very quickly calms down, carefully using his tools to identify the enemy and his powers, and is able to think several steps ahead, having baited Narancia to attack Risotto Nero by taking advantage of his own weak position and predicting Risotto's moves. However, Doppio is also quick to anger, but unlike Diavolo he is less controlled and focused with it. Snappy, Doppio flat-out disobeyed and argued with his direct superior during the battle with Risotto, and he berated Buccellati for nearly falling into the street. He also has low tolerance and almost zero patience for "idiots" and people who withhold "phones" from him.

Doppio has been shown questioning fortune telling, as he stated that some of the guesses the fortune teller made were simply that due to his appearance ("you're a tourist" because of his bag, "you have a secret" because everyone does, etc.).

Even with the bridge of personality to personality, however, he is seemingly unaware of their co-inhabitance and appears to consider himself Diavolo's underboss and, furthermore, an entirely separate person. The source of this ignorance is unknown; Diavolo was shown moving Doppio out of the alley shortly after killing the fortune teller so he didn't see the corpse, but it's also possible that Diavolo withholds memories from Doppio. Doppio seems to be ignorant of what the objects he calls "phones" really are and seems to bend reality while he converses with Diavolo, being capable of hearing the Boss's voice come from whatever he's grabbed be it ice cream or a frog. He seems to have a poor memory to top it off, but whether it's due to Diavolo's ability to withhold information from Doppio is unknown: before encountering Risotto, Diavolo warned his alter ego that the assassin was in the area and gave him strict instructions on how to deal with him and how to complete the mission. However, upon "hanging up", it took one solid panel for Doppio to immediately forget his mission, what he was just ordered, the fact that Risotto was in the area, and above all how he managed to talk to the boss despite his phone being broken.

It's theorized that Doppio is the original personality or alternatively the dominant one, as the Diavolo seen in the flashbacks had fashioned his hair into a braid like his future alter ego and Doppio better fits the "honest but dim" description. However, whether this is true or not is unknown.

Relationships

 * Diavolo: While Doppio never learned the truth between themselves, he highly respects Diavolo and always called him "Boss" - though, whether or not Doppio knew Diavolo's name is unknown. Doppio also seems to be Diavolo's gopher, something he takes pride in considering how loyal he was to a point of stubbornness, and he seemed heed most of Diavolo's orders when he remembered them.
 * Risotto Nero: Both of these characters have a mutual dislike for each other. Risotto dislikes Doppio simply becasue he is connected to "the boss" and vice versa because Risotto is looking for the boss. As Risotto continues to try to kill Doppio this dislike grows to the point that Doppio is willing to risk his own life for a chance to kill Risotto.

Abilities

 * Doppio's stand Epitaph allows him to see ten seconds into the future. He is also able to communicate with his alter ego (Diavolo) when he hallucinates fake phones.

2001 (Vento Aureo)
Doppio is first seen in Sardinia, carrying a briefcase. In his introduction the audience is made to believe he is saving a child from being hit by a car, though it is later shown he barely took notice of the child and was actually saving a bug. After possibly subconsciously using King Crimson to avoid being hit by the car, Doppio caught the attention of a fortune teller. While at first sceptical, Doppio became interested in the man's fortune telling until the fortune teller tried to force him into letting him see his hands. After becoming panicked, Diavolo took Doppio's place and killed the man, leaving Doppio to chase his bug again afterwards (terrifying the small boy who was watching).

After getting into a taxi and being conned by the driver, Doppio is met by Risotto Nero. In his rush to get away, Doppio smacks his face against a rock and bleeds profusely, getting blood all over his shoes. When Risotto asks what's in an envelope (containing a photo of Diavolo) he is lead to believe it is only a bit of rubbish as Doppio manages to stick the photograph to the bottom of his foot with his own blood.

During the fight with Risotto, Diavolo tells Doppio that he has been loaned King Crimson's power in an attempt to encourage him to fight back. There is, however, no confirmed way of loaning stands other thanWhitesnake's power, which indicates that Doppio could either use the whole of King Crimson from the start or his willpower was only strong enough to use Epitaph and one of King Crimson's arms. Doppio shows great determination to defeat Risotto despite his fear and despite Diavolo warning him to escape. He also proves himself to be very resourceful, using Narancia's Aerosmith and King Crimson in combination to shoot and kill Risotto.

Upon arriving in Rome, Doppio is taken hostage by Secco, who is fighting Buccellati. As neither of them recognise him, Buccellati saves him by placing a zipper on him to punch through him and kill Seccowithout hurting him. As Buccellati had lost his sight and hearing Doppio easily fooled him into believing he was Trish, allowing him to be lead straight to Polnareff who was obviously wary of him.

When Silver Chariot Requiem swapped the souls of the inhabitants of Rome his soul got switched intoBuccellati's body, with Buccellati's soul going to Diavolo's body. After waking up from Silver Chariot Requiem's ability and standing, he was shot by Mista using Trish's body. Mista claimed that the shots would not be fatal. However Doppio bleeds out on the pavement waiting for a call from Diavolo.