If Sonic characters already know about Saitama and his strength at 91%, it can be assumed that they have heard about his incredible power and unmatched abilities. As for how Sonic characters would react to Sonic knowing about Saitama, it would depend on their individual personalities and relationships with Sonic. Here are a few possible reactions: 1. Sonic the Hedgehog: Being the hero with a strong sense of justice, Sonic would likely be intrigued by the idea of someone as powerful as Saitama. He might even see him as a potential rival or ally, pushing himself to prove that he's the fastest in the universe. 2. Knuckles the Echidna: Known for his serious and logical mindset, Knuckles might be skeptical of Saitama's strength, wanting to investigate and find out if there's any truth to the stories. He might challenge Saitama to test his strength or engage in discussions about their abilities. 3. Tails the Fox: Being a tech genius and a close friend to Sonic, Tails would probably be excited about the prospect of studying Saitama's strength. He might try to analyze and understand the scientific aspects of his power, possibly even seeking ways to enhance his own abilities. 4. Dr. Eggman: As Sonic's arch-nemesis and a brilliant scientist himself, Dr. Eggman may initially dismiss Saitama's abilities as exaggerated or impossible. However, once he realizes the truth, he might become obsessed with capturing and harnessing Saitama's power for his own evil purposes. 5. Amy Rose: A passionate and determined character, Amy might see Saitama's strength as a symbol of inspiration. She might train harder to become stronger herself or see Saitama as a role model and aspire to help others as he does. Overall, each character would likely react differently to Sonic knowing about Saitama's strength. But regardless of their initial reactions, it is safe to assume that they would all be intrigued by the idea of encountering or learning more about such a powerful individual.