Silver refers to Leona as Malleus’ friend multiple times, which Leona always denies.
Kalim refers to himself as Leona’s friend, but whenever Leona himself references their supposed “friendship,” it is sarcastically.
He also refers to Vil and himself as friends who understand one another but Vil replies that the complete lack of emotion behind his words is creepy, so this was also likely sarcastic.
During Book 7 Azul reacts with surprise that Leona would risk himself to save someone else (in reference to Ruggie) and Leona responds, “I would never abandon a true friend. Right, Ruggie?,” but this was possibly a sarcastic callback to the events of Book 2.
An annoyed-looking Ruggie responds, “Are you being serious right now?” and does not seem to believe him. Much like the interaction with Vil, Leona’s sincerity is questionable.
Kalim refers to Jack and Leona as his friends during Playfulland and then asks why Leona’s expression has changed: “You’ve got a funny look on your face. Did you swallow something gross?”
Ace refers to himself, Deuce, Jack, Grim, the prefect and Ruggie as Leona’s friends in Book 2 when mocking him about Cheka. Leona is not pleased.