Diavolo lives most of his life in the shadows, hinted to perpetually travel across Italy hidden in Doppio, his alternate personality, and sleep in motel and hotel rooms exclusively.

Even in the already secretive Passione hierarchy, Diavolo goes to excessive length to hide his identity and his face, issuing orders through several proxies or by computer so that nobody ever meets him personally. As he believes the mistakes of the past or simply the past itself is something to be defeated and destroyed in order for human beings to grow, he is exceptionally anxious about his past, linking it to fear, and being apprehensive of anyone learning of him. The biggest personality trait Diavolo shows is his obsession with erasing any trace of his history and keeping his presence a secret from the world, a compulsion he tries to fulfill by any means. Subordinates never interact directly with Diavolo, not even capos even when you break it to pieces and entomb it in stone, it crawls out like a worm. In order to grow, we must defeat the mistakes of our past. He also shares a pair of studded pants and seemingly sock-less loafers with Doppio. On his arms are floral sleeve tattoos leading down to a pair of gold wristbands.

His shirt, hidden under Doppio's sweater, appears to be made of complex mesh-wiring: it covers his shoulders and torso but down his back and abdomen are linked circles that are tucked under his belt, which in the back end in two~three long 'coat tails'.

The rest of his hair is cut straight across at his shoulders. He has long hair, leopard-patterned with various spots, parted in a zig-zagging manner the bangs of which are propped and parted slightly to the side. Diavolo is a tall man with a lean and semi-muscular build.

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