Serafall's aggressive attitude toward Leo caught everyone off guard.
No one had expected Sona's older sister to treat him so coldly. After all, Leo and Sona had always gotten along well. By all logic, Serafall should've been friendly with him too, especially considering his potential. Even now, he was strong enough to defeat a fallen angel executive with ease. For the Maou who upheld the devil world, talent like that should have been cherished.
And yet...
This reigning Maou seemed openly hostile toward him.
The others exchanged puzzled looks, silently asking each other what was going on.
"Big Sister!"
Sona finally couldn't take it anymore. She stepped forward and dragged Serafall aside.
"Ow, So-tan, you're hurting your big sister~~~"
Serafall put on a pitiful expression as she was pulled away.
Sona didn't buy it for a second.
"If I were capable of hurting a Maou, that would be impressive," she said flatly. "Stop pretending to be weak. And stop treating Leo like that. As a Maou, you should show some magnanimity."
"But I'm mad!" Serafall puffed out her cheeks. "He's trying to steal my So-tan!"
"Steal me?" Sona shot back. "Has he done anything wrong?"
"You're so mean, So-tan!" Serafall huffed. "You're smart. Don't tell me you haven't realized the family already sees that bad guy as your future fiancé. They're planning to have you two get engaged!"
Sona fell silent.
Of course she knew.
As the next head of the Sitri House, and someone sharp enough to catch the faintest shift in the wind, she could easily piece things together. Unless the family deliberately hid everything from her, any hint was enough for her to see the bigger picture.
She had always understood that even after canceling her previous engagement through her own efforts, the family would never let her remain single forever.
The once-glorious Seventy-Two Pillars had already lost over half their bloodlines. The number of pureblood devils was shrinking year by year, replaced by half-devils and servant devils. In times like these, every pureblood devil family feared their lineage would end in their generation.
For them, producing the next generation of pureblood devils was paramount. There was no way they'd allow an eligible heir to stay unmarried indefinitely.
Marriage alliances between pureblood families were unavoidable in today's devil world. Even a prosperous family like House Phenex eagerly arranged engagements to secure their future.
So Sona had always known.
Even if she fought off one engagement, another would eventually come.
All her struggle had really done was buy time and change the candidate.
It wasn't just her. Rias had been the same. Even if she resisted her engagement with Riser, success would've only meant being matched with someone else. That was the unavoidable duty and fate of pureblood devils.
If not for Issei winning over the Gremory House in the original story, Rias would never have gained true freedom in marriage.
As for Sona...
She had been quietly delaying the inevitable, maneuvering behind the scenes where no one could see.
She had prepared herself to keep resisting. Yet unexpectedly, the Sitri House stopped searching for a new fiancé for her.
How could she not be suspicious?
Once suspicion took root, it didn't take much deduction to understand their plan.
They weren't looking for a new candidate because the chosen one was already by her side.
They allowed her freedom because her relationship with Leo was progressing smoothly. The two were growing closer on their own. When the timing felt right, the family would simply bring it up and let things fall into place naturally.
After realizing all this, Sona thought it over again and again.
And in the end...
She chose to allow it.
"If I'm going to be engaged no matter what," she murmured quietly, "then why not choose someone I don't dislike?"
That was her answer.
If she had to have a fiancé, she wanted it to be Leo.
At the very least, she knew him well. She admired him. Over the past few years, their time together had been nothing but pleasant. There was no reason to introduce unnecessary complications.
In other words...
Leo wasn't just the future son-in-law chosen by the Sitri House.
He was the future husband Sona herself had chosen.
Otherwise, with her cool and strict personality, how could she, like Rias, have let him see her completely bare without the slightest concern?
Only because it was Leo.
Anyone else?
Not a chance.
But Serafall couldn't accept it.
"No, no, no! So-tan belongs to her big sister! Not to anyone else!"
She clung to Sona dramatically, looking like her heart had been shattered.
Sona pressed a hand to her forehead.
"Whether I belong to you or not aside, if you don't want me to marry, you should talk to Father. This isn't something I can decide."
"Ugh…"
Serafall deflated instantly, sighing. "You think I haven't tried? Father won't even listen to me!"
"Because you're being unreasonable," Sona replied mercilessly. "Ever since you became a Maou, I'm the only one left of our generation in the Sitri House."
"You're not like Sirzechs-sama, who's already married and has a child. If I stayed single like you, who would carry on the Sitri House?"
"We can't exactly hand the lineage to a branch family. Father would kill both of us."
Serafall was completely speechless.
Sirzechs had taken the surname Lucifer and ascended as a Maou, but he had married Grayfia and already had a son. That child was considered the safeguard of the Gremory House, the heir after Rias, even carrying the Gremory name.
But Serafall?
Her rival Grayfia had long since married and had children. Meanwhile, she spent her days playing magical girl, smiling and having fun, not even bothering to find a partner. How could their father possibly approve?
If she weren't already a Maou, she would've been forced into hundreds of matchmaking meetings by now.
Their father might not be able to control Serafall...
But he could certainly control Sona.
He had already given up on one rebellious daughter. If that daughter tried to drag his only remaining one into staying single too, he might truly disown her.
In short, the Sitri House had made its decision. Even a Maou couldn't change it unless she was willing to sever ties with her family.
And that was exactly why Serafall kept glaring at Leo.
"I just can't stand the thought of someone stealing my So-tan…"
She sniffed, on the verge of tears.
"No matter what, you're not allowed to cause trouble anymore," Sona said seriously. "This is the best possible outcome right now. If your selfishness ruins it, I won't forgive you either."
She hadn't taken any concrete steps with Leo yet, but she was satisfied with how things were progressing.
She didn't want to rush into defining their relationship. She wanted to continue like this, steady and natural, until an engagement simply made sense.
If Serafall's antics ruined it, she really might resent her.
Because if this fell apart, she might truly end up marrying someone she disliked, or worse, someone she didn't even know.
And that was something she absolutely refused to accept.
"…Fine."
Seeing the resolve in Sona's eyes, Serafall finally wilted.
"I won't oppose you being with that bad guy anymore, okay?"
Her heart felt like it was breaking as she said it.
Her beloved little sister would still be married off one day.
But if that outcome couldn't be changed, then at least Sona should marry someone she liked. Seeing her smile would be some comfort.
"So-tan… promise me something."
Resigned, Serafall took another approach.
"Don't give yourself to him too soon, okay? Let big sister have you for a few more years. Don't rush into having kids, please~~~"
She clung to Sona and started crying again.
Sona's face turned red, an extremely rare sight.
"What are you even saying, Big Sister?!" she snapped, flustered. "There's no way I'm thinking about having children now! I haven't even graduated high school!"
She still planned to attend university in the human world. How could she possibly get married so soon?
In her plan, she would confirm her relationship with Leo during college, marry after graduation, and only think about children afterward.
That was at least four or five years away. Her sister was worrying about nothing.
"Really?" Serafall narrowed her eyes suspiciously. "Then swear you won't give yourself to that jerk before marriage. Not even holding hands!"
Sona took a deep breath, barely suppressing the urge to commit sororicide.
Even someone as composed as she found that outrageous.
What kind of person wasn't allowed to hold hands before marriage?
If she told her that Leo had already seen her completely naked, wouldn't Serafall explode?
"I'm telling Father," Sona said coolly, raising her hand. A small communication magic circle formed above her palm.
"W-Wait!" Serafall panicked and grabbed her hand. "No need for that, So-tan! I misspoke! Holding hands… gulp… holding hands is fine…"
She looked as if she'd made the ultimate sacrifice.
Sona finally gave up.
"You should go back first, Big Sister."
She was done. Truly done.
Her sister had embarrassed her before, but this was unbearable.
Why did I end up with a sister like this?
At this rate, maybe she really should just give herself to Leo already…
Then her sister would have no choice but to accept reality and stop being so annoying.
With that thought, Sona's gaze drifted toward a certain someone.
"Ah-choo!"
Leo, who was chatting with Rias, suddenly sneezed. He rubbed his nose and muttered, "Who's thinking about me now?"
Cao Cao? Or Vali Lucifer?
Yeah… next time, I'm definitely beating them half to death.
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You can read up to chapter 230 on patreon.com/NiaXD.