Another of my head cannons from One Piece where Franky is partially a cyborg. He lost his left hand and his right leg. He substituted them with for a robotic arm and leg, which constituted part of BF -36. This is after the the AU time-skip where he updates his arm and leg after almost being killed during the explosion in Vegapunk's lab. In addition to his star tattoo I added another alluding to the events that led to him eventually losing two of his limbs. Somehow I doubt he'd forget what happened to Tom-san.
With my short explanation out of the way... Enjoy, guys!