Skull is the holder of the Purple Pacifier. Head of the Combat forces of the Calcassa Family, Skull wears a full leather outfit and a motorcycle Helmet, which is copied by all his subordinates. His pet is a giant Armored Octopus whose tentacles follow his hand and finger movements. He is implied to be not as powerful of an Infant as Reborn and Colonnello, whom he calls his senpais, and is looked down upon and ridiculed by the two. Reborn considers Skull as being someone's errand boy, and Skull, to his dismay, does not deny the fact that the only person he was an errand boy to was Reborn. In the anime, it is known that his job was a stuntman; he also gained the nickname " Skull from Hell".
Skull is first seen in his assault on Mafia Land for the Calcassa Family. He faced off against Reborn, but lost horribly when he was made unable to give commands to his pet octopus. Colonnello simultaneously obliterates all his sea forces.
In the Future, Skull is said to have died. The Millefiore possesses his Cloud Pacifier.
During the Arcobaleno Trials, Skull is second to test Tsuna. He hired Viper to turn into Tsuna and get Hibari and Mukuro angry and challenge him. Tsuna used X-Burner to defeat Skull's Armored Octopus. After his defeat, he tried to run away however, he was beaten by Reborn and Colonello because he insulted them. He later helps out in the fight against Verde, though his ship is easily destroyed by Box Weapons mistakened for missles. He is captured along with the other Arcobaleno, though his helmet protects him from the radiation similiar to the Anti-Tri-Ni-Set until Verde removes it.
Skull and the other Arcobaleno are called by Reborn to train Tsuna and the others. He is paired up with Hibari, as the both have the Cloud Flames. Hibari is shown to intimidate Skull, and Skull is shown to irritate Hibari, creating a caustic relationship. Later, at a meeting of the Arcobaleno tutors, he tries to tell of his training with Hibari, but is interrupted by Reborn before he can do so.
After Byakuran was defeated, Skull and the rest of the Arcobaleno were revived because Uni sacrificed herself to bring them back to life.
- Armored Octopus - Skull has a Giant Armored Octopus as his Animal Partner and uses it for a majority of his combat by controlling it with specific finger movements.
- Purifying Helmet - In Episode 151, during the Arcobaleno Trials when Verde, in an attempt to kidnap the Arcobaleno, tried to use a mineral with properties similar to the Anti-Tri-Ni-Set radiation, Skull was seemingly unaffected. It was then shown by Verde that Skull's Helmet that he is commonly seen wearing as a baby has Purification Abilities.
- Armored Muscle Body - In Episode 152, Skull shows his special Ability. He gains a large amount of muscle, though he stays the same size. While under it's effects, Skull seems to be impervious to all damage, to the point where being knocked into a stone hard enough to shatter it doesn't phase him. He can also be hit by a powered up Box Weapon several times and only be mildly annoyed afterwards.
- Even though Skull is a leader and the strategist of Calcassa Family, he appears to be an errand boy (even with the other Arcobaleno, besides Reborn and Colonnello), though Fon seems to be indirectly against it.
- He's the noisiest among the Arcobaleno, but not the overall the characters, which is taken by Squalo.
- Reborn says that Skull is his lackey.
- He seems to regard Lal Mirch as an older sister figure, referring to her as Lal-oneesan, and he will look to her for protection from Colonnello and Reborn.
- He seems to be the weakest Arcobaleno among the others.
- Openings Features In: