Bianchi is Reborn's hopelessly devoted lover, and tried to kill Tsuna to be with Reborn. She is also called The Poison Scorpion and uses poison food as her main arsenal choice of weaponry. Currently she is a ally of Tsuna's Mafia family and is often seen as a mother figure helping the younger girls and protecting them while Tsuna is fighting. Bianchi is the older sister of Gokudera.
an extended description!