Sonic groaned for what felt like the hundredth time that day. Every part of him ached; his face felt as swollen and puffy as a boxing glove, his peach chest was an impressionist painting of yellow and purple, his legs throbbed every time he shifted on the couch. Somehow, he hadn’t come out of this with a twisted ankle or broken leg. Sonic was pleasantly surprised- previous beatings almost always fucked up his legs.
After bandaging Sonic up to the best of his ability, Shadow had disappeared into the kitchen, clinking around doing who-knows-what. He returned now, holding two steaming mugs. He gave one to Sonic. “Drink.”
Just to be contrary, Sonic took his time examining the mug first. It was one of those “World’s Best Dad” mugs, except “dad” had been crossed out for “thief”. Rouge’s then. Sonic finally took a sip, and immediately sputtered. “What is this?”
“Ginger. It’s good for inflammation.” At Sonic’s face, Shadow scowled. “I didn’t over-steep it and I added honey. It’s not too strong. Drink.”
Sonic grumbled but obeyed. Without a frame of reference, Sonic wasn’t sure what Shadow meant by “too strong”, but he could taste the honey in the tea, and once he got used to it, the almost-spiciness of the ginger was nice. He took another sip.
Shadow settled into the chair across from where Sonic was laid out on the couch. He drank from his own mug, black with small blue flowers, and set it down on a coaster on the coffee table. His eyes met Sonic’s, and he leaned forward. “Talk.”
Sonic squirmed. “Do we have to?”
Shadow’s glare could have shattered steel. “You threw a fight and asked me to beat you up. That is not normal. Explain.”
Sonic shoved his face back into his mug. He’d been dreading this bit, ever since Shadow had threatened him with it at the end of their- fight? Beating? What was that? What had possessed Sonic to roll over and ask Shadow to treat him like a second-rate punching bag? 
He lowered the mug with a sigh. “I don’t know.”
“Figure it out,” Shadow spat. He inhaled sharply, closing his eyes as if gathering his patience. “Look. Is this some kind of… pleasure thing? Rouge told me that some people-”
“No no no no no!” Sonic said, throwing up a hand to hide his returning blush, which failed as the quick movement sent shocks of pain up his arm that forced him to drop it. He hunched over, trying to shield his burning face as best he could. “I-it’s not that. It’s not.”
Shadow stared at him.
“It’s not!” It wasn’t. Sonic wasn’t aroused during the beating, not until the end at least, when Shadow had held him up like a broken doll and spat in his face. That had made Sonic’s crotch throb, and even the memory of it made him squirm.
“You don’t need to lie, hedgehog,” Shadow sighed. “We’re both adults. We can talk about… sex. We have to, if that’s what this is.”
Sonic wanted to die. “I swear I don’t get off on pain,” he said, refusing to meet Shadow’s eyes. “I wasn’t feeling anything like that until the end, when you- when you…”
“When I?”
“Whenyouspatinmyface,” Sonic mumbled as quiet and quick as he could. The ensuing silence was almost physically painful. He gathered the courage to look at Shadow, only to find an unreadable expression on the black hedgehog’s face. “Uh, Shadow?”
Shadow sighed. “Very well. We will return to that. If you are not a masochist, then why did you ask me to hurt you?”
Sonic winced at his bluntness, wishing he wasn’t a mass of aches and bruises so he could run away from this conversation. “...I wanted you to.”
“Clearly. Why did you want me to hurt you? Is it- were you ‘self harming’?”
“It’s not self if you’re the one doing it to me,” Sonic quipped, then flinched at the poison in Shadow’s glare. “Sorry, sorry, I know, outta line. No. I don’t think that’s it.”
“Why not?”
Sonic’s face screwed up in effort as he thought. “…If I wanted to self harm, I wouldn’t have asked you to do it.”
He looked up, seeing a blank stare on Shadow’s face. He sighed; he only half understood himself, but the more he talked the more right it felt. “Getting beat up’s my job. If I wanted to hurt myself I’d just have to put myself in danger. You’re different. I- I know I can trust you.”
“You trust me to beat you up.”
Sonic rolled his eyes at Shadow’s deadpan. “I trust you not to hurt me.” At Shadow’s blank stare, he huffed and gestured at his legs. “Look. You didn’t hurt my legs, that’s like, step one for Giving Sonic a Beating and you didn’t do that. I don’t think I’ve got any broken bones. Afterwards you were all fussy about making sure I wasn’t internally bleeding. You didn’t hurt me.”
Shadow was silent for a moment. He looked away from Sonic, digesting. When he spoke again, his voice was almost subdued. “That doesn’t explain why you wanted to be beat up at all.”
Sonic shrugged. “It’s my job.”
Shadow grimaced. “You realize how that sounds, right?”
“What?”
“Don’t ‘what’ me. Are you claiming your entire role in life is getting beat to a pulp?”
“Kinda?” Sonic laughed; the tension in Shadow’s face didn’t lessen. Damn. “Look, I don’t get like this often. Most of the time I’m how you expect. Independent. Adventurous. Arrogant. Free.” He sighed. “But sometimes, I get this itch. Like I need someone to put me in my place. Remind me I’m nothing.”
Shadow sat still, digesting again. “You know you aren’t nothing.”
Sonic scowled. “I know. But sometimes I am. Sometimes I need to be.”
Something flashed in Shadow’s eyes. “And you need to be safe when you are.”
“Yeah.” Sonic let out a breath, suddenly feeling like he’d lapped the planet. Twice. He fell back into the couch, nursing his tea. “This is exhausting.”
“Hmph,” Shadow scoffed, though he looked as worn as Sonic did. He took another sip of tea, apparently content with that end to the conversation, staring into the distance as if pondering some secret. Sonic himself set about finishing the rest of his tea, thinking over the rest of the day. He’d been staying at Tails’ workshop- hell, how was he supposed to explain this to Tails? “Hi bro, sorry I look like this, I got beat to shit by Shadow, please don’t kill him, I asked for it?”
Abruptly Shadow stood. “If you feel like this again, call me.” Ignoring the blush returning to Sonic’s face, he turned and headed towards the bedroom. “You’re free to stay the night, if you wish. Just don’t disturb me.”
“Wait, what are you doing?”
“Research.”
The shudder that ran through Sonic had nothing to do with pain.