He should have known better than leave Sonic roam the Floating Island on his own. He had no idea how the blue hedgehog got the information or what forces made him draw the conclusion and probably never would now. All he did know was that he had definitely been unaware of… well, anything, before his short stroll, so the stroll had to be the cause.
He'd become sloppy, too used to Shadow visiting. Shadow could be left to his own devices. Shadow was good at figuring things out, but he knew how to take a hint. Shadow knew how to leave things well alone.
But Sonic wasn't Shadow. And it was too late now.
"Were you ever going to tell us?"
It wasn't the question itself but the serious undertone that caught Knuckles off guard. He whirled around before he could catch himself, only to be faced with an eyebrow arched and a restless tapping of a foot.
"What?.."
"I said," Sonic repeated, his patient voice contrasting sharply with his body language, "Were you ever going to tell us?"
"I have no clue…"
"Eggman," he said simply, succinctly, then paused and waited. Sure, his body still radiated impatience and he seemed unable to stop moving even for a moment, but the action, or rather lack thereof, seemed so uncharacteristic that Knuckles couldn't help but let his jaw drop slightly. What on Mobius?..
Some of the vibrating tension seemed to dissipate as Sonic let out a small sigh, apparently seeing no understanding dawn.
"When you said he had crashed on your island," he clarified, his voice still oddly controlled if with a tiny bit of annoyance shining through. "Was there another thing that you simply forgot to mention?"
Bafflement gave way to irritation in a matter of seconds.
"I don't see how this is any of your business," he said, already turning on his heels to walk away.
"This is precisely what I am talking about!" was yelled into his back, the annoyance now clear.
He didn't turn. He wasn't followed. He knew better than expect it to last.