The thing about Billy Hargrove—post-Starcourt, post-trauma, post-finally-letting-himself-be-a-human-being—was that he’d gotten really good at not reacting. Especially around Steve and Robin, who had made it their personal mission to crack him like he was some kind of grumpy, denim-clad safe full of blushes and secrets.

They’d been failing for nearly twenty minutes.

“You know,” Steve said, leaning against the counter like a man who believed leaning counted as a personality trait, “most boyfriends blush when their girlfriend compliments them.”

Billy didn’t look at him. “Most guys named Steve mind their business.”

Robin snorted. “Okay, okay, but what if—just what if—” She gestures wildly. “—you finally admitted that you actually like being flustered?”

Billy raised one eyebrow. “I don’t get flustered.”

Steve gasped. “Oh? Oh really? So if I said you’re looking especially sun-kissed today—”

“Don’t,” Billy warned.

“—and that your hair looks like a shampoo commercial—”

Robin slapped a hand on Steve’s chest. “You’re embarrassing yourself.”

Billy didn’t blush. Didn’t twitch. Didn’t even blink. He just leaned back in the loveseat in your living room, legs spread, arms draped over the backrest like some smug beach-groomed cat who’d found a warm patch of sun and dared anyone to move him.

You watched all of it from the doorway.

They weren’t wrong—Billy didn’t blush easily anymore. Not since he’d figured out how to keep himself steady. Not since Hawkins stopped being a battlefield and started being something like a home. But you knew something they didn’t

Billy’s tells weren’t physical.

They were electrical.

A slight delay when he was surprised. A too-long blink when he was overwhelmed. A breath caught in his throat followed by his brain effectively hitting a restart button.

And they were seconds away from seeing it.

Steve threw his hands up. “Okay, I give up. Dude’s made of stone.”

Robin nodded. “Like a hot statue. But still a statue.”

Billy sighed. “You two done?”

You knew it was time.

Pushing off the doorway, you walked toward him with a calmness that made Steve’s eyebrows pinch in suspicion. Billy’s eyes tracked you carefully—subtle, slow, like he wasn’t sure yet what game you were playing, but he already suspected you were going to win.

When you reached him, you didn’t say a word.

You just slid your fingers under his chin—gentle, deliberate—and lifted until he was forced to look at you. His breath hitched, barely noticeable unless you were listening for it. Which you were.

His lips parted.

His body stilled.

Your face hovered just a breath from his, warm enough that his lashes fluttered.

And then, softly—dangerously softly—you whispered

“My good boy.”

Billy blue screened.

There was no other word for it. His brain shut off. His pupils widened, posture slumping just a fraction as if his bones had melted. His breath left him in one shudder, and the color blooming at the tops of his cheeks betrayed him instantly.

Steve made a strangled noise.

Robin slapped both hands over her mouth.

Billy didn’t move. Didn’t speak. Didn’t even seem conscious for a full, magnificent second.

“…Jesus Christ,” he muttered, voice wrecked, “you can’t just—say that—”

Steve pointed. “THAT! THAT RIGHT THERE! He blushed! He malfunctioned!”

Robin was wheezing. “Someone reboot him!”

Billy dragged in a breath, eyes sharp, cheeks flushed, every muscle actively fighting the urge to hide his face in your shoulder.

You leaned in, brushing your nose against his.

“That’s because you’re mine,” you whispered, “and because you’re perfect.”

Billy’s ears turned pink.

Steve and Robin both screamed.