Ryuichi closed the door behind him. The blonde girl who had been hurrying over suddenly froze the moment she saw him.
"Who are you?"
She blinked in surprise, her gaze darting to Sakurajima Mai standing beside him, confusion filling her eyes.
"Nice to meet you. I'm Ryuichi," he said casually. "I'm dating Mai."
"What—huh!? You? There's no way someone like you could be sis— I mean, could be Mai-san's boyfriend!"
Her disbelief was almost comical. Ryuichi noticed, though, that she'd called Mai Mai-san, not onee-chan.
So there's some story here, huh?
Even though the girl's words were pretty rude, Ryuichi didn't seem the least bit annoyed. He just took the bag Mai handed him and hooked it neatly onto the wall rack by the entryway.
"What kind of guy do you think would be worthy of being your sister's boyfriend, then?"
His easy tone caught the girl off guard, her mouth opening and closing like she couldn't find a retort.
"A-anyway, definitely not someone like you!"
"I bet in your mind, no guy is ever good enough for your sister. Right, sis-con girl?"
"…"
Bullseye.
Her face stiffened, her lips twitching like she'd been hit dead center.
"Wh-who are you calling a sis-con!?"
Ryuichi couldn't help but laugh. "You mean to tell me you don't secretly want your sister to stay single forever?"
"N-no way!"
Watching her little sister's face flush from Ryuichi's teasing, Mai sighed helplessly. "Ryuichi, stop bullying her already."
She reached out and gave his cheek a gentle tug before stepping in to introduce them properly.
"This is Toyohama Kazuka—my half-sister."
Ryuichi nodded toward her. "Nice to meet you, Kazuka. Make yourself at home, yeah? Pretend this is your own place."
Kazuka just blinked, utterly speechless.
Was this guy serious? He was acting like he owned the place!
"…Mai-san, this guy's really your boyfriend? Are you sure that's okay?"
Her eyes ran up and down Ryuichi like she was trying to spot something redeemable about him. Handsome, sure—but besides that? Not much came to mind.
There's no way sis could fall for someone this shameless, right? Did he somehow trick her?
As she spiraled through increasingly dramatic mental scenarios, Mai just sighed again. "Hey, don't badmouth my boyfriend right in front of him, Kazuka."
Still standing by the entryway, Mai propped one hand on Ryuichi's shoulder as she bent down slightly, slipping off her heels with practiced grace. Ryuichi quietly pulled her soft house slippers from the shoe cabinet and set them at her feet.
"I'll make dinner," Mai said after putting them on, carrying the grocery bags toward the kitchen.
That left only Ryuichi and Kazuka—locked in a silent, mutual stare across the living room.
"I'll go help," Ryuichi said immediately. There was no way he was staying out here alone with that sister-complex girl.
Inside the kitchen, Mai hung her handbag aside and tied on an apron.
Leaning against the wall, Ryuichi watched her every move. His eyes didn't stray for a second.
"You really look like a wife right now," he murmured.
"Oh? Do you like seeing me in an apron?" she asked softly, washing vegetables as if unaffected by his flirtation.
"I'd like it even more if you were only wearing the apron."
"…What?"
Mai turned her head, giving him a tired look that clearly said I can't believe you sometimes.
"Don't say stupid things."
Ryuichi just grinned and opened the fridge. Inside, neatly lined cans of a soft drink caught his attention—each one printed with a familiar face.
Sakurajima Mai.
Her current endorsement brand.
Ryuichi blinked in amusement and pulled one out, cracking it open.
"You like that one?" Mai asked, glancing at him. "Dinner's almost ready, you know."
"I didn't—until I saw your face on it. Suddenly it tastes amazing."
He said it dead serious, and Mai's lips curved into a small smile.
"They were just free samples from the ad campaign," she said lightly. "We each took a few home because there were too many left over."
"It's fine," Ryuichi said with mock solemnity, raising the can. "If it's got my wife's face on it, I have to drink it."
"Then maybe I should do a commercial for lemon water next time," she mused with a teasing smile.
"…Is it too late for me to take that back?"
"Way too late."
Her voice was pure mischief, but her smile was gentle—radiant even. Being called wife had clearly made her day.
From the living room, Kazuka sat pretending to watch TV, but her ears were locked on the kitchen conversation the entire time. The corners of her mouth twitched.
So that's it—he's just a smooth talker.
How could Mai fall for a guy like that?
By the time the couple finished cooking, Kazuka was still pouting quietly, glaring at them across the table.
Seeing her expression, Ryuichi asked evenly, "Something bothering you? You can tell us—maybe it'll make us happy."
"…"
Grinding her teeth a little, Kazuka stabbed a slice of meat, chewing with extra force—like the poor cutlet was Ryuichi.
"I'm not mad," she mumbled finally. Swallowing, she glared at him again. "I'm just saying, Mai-san's career is really taking off right now. You'd better not cause her any trouble."
"Kazuka, eat your food," Mai said calmly. "Ryuichi and I both understand what you mean."
What Kazuka didn't know was that Ryuichi had been quietly supporting Mai behind the scenes all along—something Mai herself knew better than anyone.
Ryuichi didn't bother defending himself, but Mai couldn't stay silent. If she didn't speak up, what kind of girlfriend would she be?
"You two seem close," Ryuichi said after a moment. "Then why don't you call her onee-chan instead of Mai-san?"
That question froze both sisters mid-bite. Neither seemed to know how to respond.
Seeing their awkward silence, Ryuichi chuckled softly.
Thinking about Mai's strained relationship with her mother, he gave her a wry look.
"…Your family really is something else."
"…"