As one of the Millefiore's genius mechanics, he was responsible for the creation of the Famiglia's Moska units, including the King Moska and the Mini Moska (in the anime). Currently, however, Spanner has been recruited into the Vongola Famiglia by Tsuna after the transportation of the Merone Base by the Hyper-Flame Ring Transfer System. Spanner is described as a "relaxed" character who doesn't get as worked up as Shoichi Irie. It's revealed that Spanner and Shoichi go way back and met each other at a robotics competition in high school. They were also in the Tech Department together when they both just joined the Millefiore.
Merone Base Invasion Edit
When the Merone Base is infiltrated by the Vongola, Shoichi turns to Spanner, asking him to locate and eliminate Tsuna. After a long battle, Tsuna eventually defeats Spanner's King Moska and falls unconscious. Prepared to kill him, Spanner decides against it and takes him back to his workshop, where he handcuffs him until he wakes up. His motives for doing so eventually become clear when he reveals that he's planning on helping Tsuna perfect his X Burner, the new technique he acquired and used against the King Moska. Admitting that he's a techno- and Japanophile, he tells Tsuna that he's interested in the power of the Vongola and didn't kill him because killing someone with a gun just isn't his style.
In order to help Tsuna perfect his X Burner, Spanner develops a pair of contact lenses for him that will help him gain control of the flames in each of his gloves. In the middle of working on this project, Iris and Ginger Bread show up to take Tsuna and kill Spanner. Rather than running away, he sacrifices himself to complete the contacts and is surprised when Tsuna protects him. Sadly, Mini Moska dies from trying to protect the one who made him (in the anime). After Tsuna unleashes the power of the fully complete X Burner, the two head out in search of Shoichi and his laboratory. Along the way, they run into Genkishi, who Tsuna faces off against in an attempt to get to their destination. Eventually, they make it to the laboratory, where they find the other members of the Tsuna's family, and Shoichi himself.
After the disappearance of the Merone Base, Spanner and Shoichi are left homeless and jobless. Tsuna accepts them into the Vongola and the two work together to conceal the time machine that was in Shoichi's laboratory. After this task is complete, Spanner, Shoichi and Giannini begin preparing for the upcoming Choice battle with Byakuran. This leads to a competition over who can come up with the better invention. After 10 days of barely sleeping, the three finish and pass out at the Vongola base. Unlike Shoichi, who's shown to be sleeping in a state of half-undress up against the wall, Spanner is shown to be curled up in bed with a night cap on.
As a new member of the Vongola Famiglia, Spanner is made to participate in the Choice battle with the Millefiore. After the entire family gathers, they're transported to the Lightning Field, where the participants of Choice are to be selected. Byakuran and Tsuna spin the Gyro-Roulette and two "non-elemental" members of the Vongola are chosen. Shoichi suggests that both he and Spanner could participate, and Tsuna agrees.
While Takeshi Yamamoto, Hayato Gokudera and Tsuna take the offensive, Shoichi and Spanner stay behind at the base, where they can observe the battle and help with battle tactics. They also operate the Dying Will Flame decoys and lasers positioned around the battlefield. After Tsuna's defeat of Torikabuto and Yamamoto's battle with Saru, Spanner and Shoichi are put under the spotlight as Kikyo begins heading their way. They plan to stall for time by making their base mobile after their last line of defense, lasers positioned around the base, proves to be ineffective. However, their speed was outmatched as Kikyo closes in on them. Gokudera intercepts the attack but is brushed aside, and the base goes down, leaving Shoichi injured and Spanner unconscious. Shoichi plans to make a run for it, leaving Spanner to "take care of the base."
The Vongola eventually lose the battle after Yamamoto strikes down Deisy, who doesn't die. After a dramatic turn of events involving Uni, the Vongola and their allies are transported back to Namimori, Spanner included. He eventually goes back to the Vongola base with Yamamoto, Giannini and Bianchi in an attempt to salvage the base and rescue Squalo. Spanner does eventually return with Yamamoto, though the part he plays in the final battle with Byakuran is limited. Before the Ten Years Later Arc comes to an end, he's seen, true to character, working on a new Moska, and nearly destroying Gokudera in the process.
Just before Uni died, she showed images to some people from the past of what happened to the future. Spanner was one of those people and thus, his past self knows everything.
Spanner communicated with Shoichi Irie and used his knowledge and experiences from what he saw because of Uni to create new gear for Tsuna. He sent the gear to Japan and he informed Shoichi that he too would be there soon, to meet them. In the recent chapter, Tsuna has a flashback of Spanner making a special set of contacts which he uses in the battle with Enma Kozato of the Simon Famiglia. The contacts allow Tsuna to fire a two-handed X-Burner called the XX-Burner.
During the 4th day, Verde commands Spanner to fire. As the object flies, Verde leaps into it and it is revealed to be a Green Moska. Verde explains that by using the latest Moska frame built by Spanner and adding his cutting-edge military technology he was able to create this super robot.