Futa, also known as Futa de la Stella, lit. "Futa of the Stars", is a young boy who ranks people by their abilities in his Ranking Book. He has an extremely wide range of knowledge on thousands of people and is considered to be an invaluable informant for the mafia, sometimes being paid insane amounts of money for a copy of certain rankings.
He has short light brown hair and large, dark brown eyes. In the future, he has grown much taller, and wears a white vest over a long-sleeved green shirt and a black tie. At present, he is mostly seen wearing a long, black-and-white striped scarf over a black sweatshirt and plain dark blue pants, or a light green shirt with a white collar and white cuffs.
He calls Tsunayoshi Sawada his big brother and has ranked him last on every aspect of combat, but was overjoyed to see that his rankings on him were wrong, not realizing Tsuna was in Dying Will Mode. Futa's book is the reason why he is constantly being chased by the mafia, so Tsuna allows Futa to live in his house.
When Futa starts ranking people, gravity around him becomes distorted, making objects around him float and images of stars and galaxies appear in his eyes. It is unknown how he actually gathers his information (some say he communicates with the Ranking Planet in the galaxy), but if he does not instantly write it down, he claims to forget about it. Rain weakens Futa, however, resulting in his rankings being somewhat incorrect and random when it rains. He also has to be looking at the person to determine their rankings. Still, when done right, his rankings are said to be 100% accurate and if a person gets hold of his book, they would have the world at their mercy.
- In the Card Games, Futa is attributed to have a Storm Flame.
- According to Futa, there are 86,202 people in the Mafia that he has seen.
- Future Futa hasn't been shown to have made any rankings thus far
- The future Futa still calls Tsuna "Tsuna-nii."
- In the manga adaption in America, Mukuro states that Futa hadn't slept in ten years; however, the present Futa is only 9.
- Mukuro also stated that Futa, in order to keep the Vow of Silence, refused to speak, causing him to close his heart; and, as a consequence lost his ability to rank. This may be a reason for why Future Futa has thus made no rankings.
- Futa was featured in Family (vs. Millefiore).
- In the Filipino version of Reborn!, Futa's name was changed to "Kuta" because Futa's name sounds obscene in the Philippines.
- Futa is most likely a reference to the famous autobiographic allegory, "Le Petit Prince" by Antoine de Saint Exupery, hinted by the fact that the chapter he appears in is named "Le Petit Prince Futa," as well as wearing a scarf similar to the Little Prince's. The book is about a boy who lives on a small planet and travels from planet to planet, learning an important life lesson at every stop.
- He has the same voice actor as Lavina, the mother of Hayato Gokudera.