Bianchi, alias "Poison Scorpion," is an Italian freelance assassin and Hayato Gokudera’s older paternal half-sister. Her childhood included baking innocently toxic treats for her brother, unaware her innate Poison Cooking ability infused all her food with lethal properties. This talent propelled her into the underworld, where she partnered—and briefly romanced—Reborn, collaborating on contracts. Though initially pursuing Tsunayoshi Sawada to clear Reborn’s schedule, she rejected external manipulation, operating solely on her own terms.

Tall and pale with light pink hair and vivid green eyes, Bianchi sports a scorpion tattoo boasting a heart-tipped stinger on her left arm and a heart on her right buttock. Her figure-hugging outfits pair with orange goggles to suppress Gokudera’s allergic reactions to her proximity. She blends violent romantic aggression with underlying warmth, fiercely protective of her brother and increasingly invested in the Vongola family. Future iterations reveal a composed mentor guiding Haru, Kyoko, and Chrome, counterbalancing Gokudera’s brashness with steady pragmatism.

Poison Cooking remains her signature weapon, enabling remote detonation of her toxic creations. Later, she commands a Storm Ring and the Scorpione di Tempesta box, conjuring scorpions wielding disintegrating Storm Flames. Despite culinary lethality, her marksmanship with conventional firearms remains comically unreliable.

Her motivations intertwine with unreciprocated feelings for Reborn and a turbulent bond with Gokudera, oscillating between mentorship and rivalry. Initially hostile toward Tsuna, she later aids his battles against threats like the Millefiore. Past actions include targeting Dino under Reborn’s tutelage and holding a grudge against adult Lambo for resembling ex-lover Romeo.

Evolving from a lone operative to a Vongola pillar, Bianchi drills Gokudera in the Future Arc with merciless methods to hone his guardian prowess. She participates in pivotal conflicts like the Melone Base assault and Inheritance Ceremony, deploying advanced Storm armaments. While her assassin instincts persist, her loyalty to allies and family anchors her narrative, merging lethal precision with a maturing maternal instinct in later chapters.