A serious sibling moment.

Mason was pretty absorbed with Luxuria. In fact, he was so absorbed that he missed the shower upstairs turning off. He also missed the hum of the blow-drier. And even the pitter-patter of sneaker-clad feet descending the stairs. Which made what happened next almost an inevitability.

A hand smacked the back of his head producing an audible thwack. The owner of said hand lazily strolled past him.

"Morning llorón," Viv said through a yawn. She stretched her back as she walked towards the Keurig. His sporty sister was clearly going for a run this morning. Besides her shoes, all she was wearing was a black sports bra and a pair of tiny, red dolphin shorts. This, let's say, minimalist approach to clothing caused several fights with their moms as they were growing up. So now she would save it for when she knew that they would be gone. It also caused more than a few awkward and shameful thoughts in her little brother's head. But she either didn't know or didn't care.

"Ow," Mason said pointedly. He shot his sister a withering glare but she didn't even turn to look at him.

"Oh, boo-hoo," She said dramatically as she set up a pod in the machine. "It's what you get for using so much hot water."

"Then you should have just showered after you ran. You're just gonna get all sweaty again anyway." Mason's logic was iron-clad but also completely wasted. All it earned was a scoff from the dusky, young woman.

"Boys," She said dismissively. He was pretty sure this was less a gender issue and more a water hog issue.

Black coffee in hand, Viv fished a disgustingly dry energy bar out of the pantry and sat across from Mason. She tore the wrapper with her teeth and ripped an entire half off in one bite. Not wanting to watch such gruesome carnage he turned his attention back to his own breakfast.

At least for a few bites (and one more giant one from Viv.) His sister was smiling. Actually, no. She was grinning. Evilly. Mason had now literally seen a demon look less threatening.

"What?" He asked cautiously.

"Oh, I was just wondering," She said in the same innocent tone a villain would use when the hero was already standing on the trap door above the crocodile pit.

"Wondering what?" His throat was dry and his eyes were wide. No good could come from this moment.

"I was wondering where you snuck out to last night," She asked casually but the canary feathers were already in her mouth.

"I…" Lie! Mason's subconscious ordered him. But it was no good. His poker face was too bad and his sister knew him too well. "I didn't."

"Oh no, no, no." Viv leaned across the table and wagged a single coppery finger in his face. "I finally caught the golden child breaking an actual rule. You are absolutely telling me all the juicy details."

It should not have been possible for some to look sadistically proud. But there it was. A sparkle of malicious glee shone in her brown eyes, but her toothy smile seemed genuinely affectionate. It was a rather perfect summation of the brother-sister relationship.

"Alright," Mason knew when he was beaten, but he still had one last card to play. "But I'm invoking the Serious Sibling Compact."

The Serious Sibling Compact was what happened when you had two siblings who genuinely cared for each other but also drove each other crazy. Oh, and also when one of their parents is a lawyer. They wrote it in middle school. It basically said that if they ever legitimately needed help from their respective sibling then the other would have their back. It existed as a check on the God-given right of siblings to pester each other.

"You can't just use the Compact to get out of trouble," Viv reminded him. That was one of the first rules they came up with.

"I'm not. Will you just trust me?" Mason tried not to sound like he was begging. He was marginally successful.

"Alright," Viv said with a deep sigh. "Tell me what's going on."

"Well," He took a moment to consider his options. Maybe if he took a second he could come up with a convincing lie. But it might be nice to talk about what happened. Even if his big sister was more likely to be exasperating than actually helpful. "I snuck out to see Yumi."

That earned a long, drawn-out growl as Viv threw her head back. Apparently, she couldn't roll her eyes hard enough without also getting her neck involved.

"Why?" She said pinching the bridge. "Why bother sneaking out and getting in trouble for that? You see her literally every damn day! You're not even fuc…"

An awkward silence fell between them. Viviana's jaw dropped as she stared at her little brother in stunned disbelief. For his part, Mason locked eyes with a bird that landed on the windowsill. It was nowhere near as interesting as he was pretending. But it would hopefully help him hide the heated flush that was spreading across his cheek.

"Oh my god," The young, Latina woman was so stunned she could barely speak. But she quickly refound her voice to yell at him. "YOU FUCKED YUMI!?"

"We…" Something about the term "fucked" didn't seem quite right to Mason. Even if it was technically true. "Yes. We slept together."

It took Viv several false starts, and a flurry of hand gestures, to figure out what to say next. But after a moment a smile crept across her face.

"Wait. So you two are dating?" That thought at least seemed to cheer her up.

"Yes."

"Since when?" His big sister's brain seemed to have finally caught up.

"Last night," Mason said, rubbing the back of his head. Things definitely seemed a little less romantic in the cold light of day. But as he thought back to last night he knew it was a good thing that happened.

"You fucked Yumi the same night you asked her out!?" Viv looked flabbergasted. She buried her face in her hands, with her elbows on the table and her black hair forming a curtain around her face. All Mason could see was the slow rise and fall of her bare shoulders as she let out a deep, beleaguered sigh.

"One kind of led to the other!" He explained quickly. Over the years the teen had learned to spot the warning signs of when his sister was about to lose her temper. And the **** glare she shot him as he spoke was a particularly vibrant, red flag.

"Which one was first?" The fit girl growled at him.

"I asked her out first," Mason assured her, holding his hands up in surrender. Even if he was new to the whole dating thing, he at least wasn't that tactless. "But… Well, we started kissing and… y'know…"

"Well that's good at least," Viv said, taking a calming breath. "I was about to slap, like, six kinds of shit out of you."

"So that's why I need you not to rat me out," Mason implored her. When she gave him a confused look he elaborated. "We don't want to spend our first week of dating grounded. Especially since we haven't been able to go on an actual date yet."

His big sister considered what he said for a moment. It was a good sign that she didn't shoot him down immediately. But she also didn't seem wholly convinced.

"This isn't really a Serious Sibling thing," Viv said clearly setting up for something.

"Oh come on. This is exactly what-" Mason tried to argue but was interrupted.

"But!" His sister continued. "I'll keep my mouth shut if you do three things for me."

"Of course…" Of course, Viv was going to squeeze a favor or three out of him. And the shit-eating grin on her face made it very clear she was proud of herself. "What do you want?"

"First," The Latina girl said, suddenly quite serious. "Don't fuck this up. I really like Yumi."

Mason nodded in acquiescence. After all, he was already planning on that. It was a funny request though. But he could understand it. Viv loved her brother deep down, but could usually only show it in a no-one-picks-on-my-little-brother-but-me kind of way. But she was actually nice to their neighbor. In fact, she could be downright doting (when no one was looking.) He suspected little Viv had wanted a baby sister before getting stuck with him instead. So older Viv decided Yumi was a good replacement.

"Second, I need you to keep this a secret until next week." The athletic woman was a little less threatening this time.

"Why?" Mason was genuinely confused.

"My friends and I have a standing bet about you two. If you can wait until at least Sunday to officially start dating I can make some serious money." Viv was pretty casual in her explanation. As though betting on your little brother's love life was an everyday occurrence. Maybe it was for her.

"You can't be serious." There was no way she expected him to keep this a secret for the better part of a week. Mason was finally dating a girl. And Yumi was amazing. Did she really expect him to skulk around just so she could make some money off of his relationship?

"Look," Viv said in a tired tone. "Just do this for me and I'll give you a hundred and fifty bucks out of the pot. Deal?"

That was a tempting offer. Mason was basically perpetually strapped for cash. His allowance wasn't much, and his hobbies were all pretty expensive. At one point he tried to get a part-time job. But Rayen made it very clear that his job was to get good grades and get into a good college. So even if it wasn't a ton of cash it might still be worth it.

"Fine," Mason said reaching out to shake on their deal. "But Yumi's got veto power. If she doesn't want to do this I'm not forcing her."

"Eh, good enough," His sister said. Apparently, she wasn't very concerned about what the Asian girl would say. At least judging by the very satisfied smirk formed on her heart-shaped face. But it curdled like milk at whatever was going on in that head of hers.

"And last but not least," She gave a frustrated huff. "I need your help at work."

"You do?" Mason asked.

"Yeah. My boss wants to see me help teach someone who's never done yoga before." The health nut clearly wasn't happy about needing his nerdy help in her area of expertise. And he had to admit it didn't sound that fun for him either.

"Oh come on," Mason said as he futilely prayed she would change her mind.

"Well, have fun being grounded then," Viv said calmly, nonchalantly examining her neatly trimmed nails. "Maybe you and Yumi can learn semaphore. Since you know Mamita is going to confiscate your phone too."

That made his stomach plummet. Losing his phone also meant losing access to Luxuria. He really didn't want that. But that didn't mean that he was ready to give up just yet.

"Can't one of your friends help you? Wouldn't they be better?" That was a good strategy. Try and make it seem like he was willing to help her, but that he might not be the right choice. But alas it was for naught.

"I already tried that stupid," Viv explained in a vexed tone. "All of my friends have done yoga before. Well except Izzy, and she already said no. So I was just going to wait for someone to just show up. But it's been like a month. So you're up, llorón."

"Fine," Mason had to admit defeat. "When?"

"Thursday. I'll pick you up from school." Viv was apparently done with him. The Latina pulled her phone out of the waistband of her shorts and started texting someone.