She likes Prosper in an almost romantic way, which is mutual, and they are close friends. Hornet was the one who found Prosper and Boniface in the novel.
Hornet is like a mother to Bo. She is also rather protective of him, like when she decides to stop reading to keep an eye on him when he is talking to Victor at the St. Mark's Square fountain, though she is less protective of him than Prosper.
Hornet and Scipio have a somewhat mixed relationship. Hornet drives Scipio crazy with her teasing. Also, Hornet disapproves of Scipio's arrogance and is the only one of the group who talks to Scipio with a barbed tongue. Hornet stood up for Scipio when Riccio and Mosca were angry with him for pretending to be the Thief Lord, vying all of their admiration. In the end, She stays together with Scipio, Bo, Prosper, Riccio, Mosca, Victor and Ida as a new family.
She and Riccio are best friends and , but when Riccio is upset that Scipio lied to them, she comforts him. They must have known each other for some time since Mosca share a friendly relationship. She was living with Mosca and Riccio before Scipio found them.
Hornet most likely looks up to Ida as a mother figure. It is noted that she helps Ida with her job, such as hanging up developed pictures to be dried.
It is noted that she thinks of Victor as a friend following him and Ida taking her from the orphanage. It is possible that she looks up to him as a father figure. Even with a major ego, Victor is warmhearted.