Leon returned to the second floor. It was already late at night, and the hallway lights were off.

It was long past bedtime, so Leon figured Vivian and Fio were already asleep. He made a point of keeping his footsteps light so he wouldn’t disturb them.

But as he was about to pass Fio’s room, Leon heard a sound coming from inside—a girl’s faint sob.

Could it be Fio? Leon noticed that her door was ajar. He walked over and peered through the gap, only to find a scene beyond anything he’d expected.

The room was dark, with no lights on. Even using his Night Vision skill, Leon could only make out a blonde girl in her pajamas straddling a silver-haired girl.

One was well-endowed, the other flat as a board. Who else could they be but Vivian and Fio?

Why was Vivian in Fio’s room at night? They’d only met today!

Leon held his breath and slowed his heartbeat. As a swordsman, he’d trained in the Heart of the Clear Mirror and Still Water. No matter how intense the outside influence, he could bring his body to a steady state.

Vivian was straddling Fio, wiping away her tears, her emotions in turmoil.

He had no way to figure out why this was happening. All he could do was inch closer, carefully, hoping to understand the situation from what he could hear.

Vivian was an excellent swordswoman too, so Leon didn’t dare get too close. He watched from what he hoped was a safe distance, but the few words he could make out came in broken fragments.

It’s fine. I can work out what they’re doing from those words, Leon told himself. He didn’t want them to notice him, either.

“Shut up—don’t brush me off—”

Vivian’s voice cut off Fio as she tried to speak. For a moment, Leon thought the two of them had started arguing.

But what happened next left him dumbfounded.

“—I’ll take your first time—”

Vivian murmured in a very suggestive tone, leaning close to Fio’s ear. She bent toward her and stroked her face as tenderly as if she were her lover.

What the hell!!! What is my little sister doing with Fio?!

If the Heart of the Clear Mirror and Still Water hadn’t been active, Leon would’ve kicked the door open and charged in.

He knew that girls could fall in love with other girls. He’d seen that sort of thing in those little dirty manga before—those forbidden yuri romances between girls.

What he was seeing now was exactly like something out of a yuri manga: Vivian sneaking into Fio’s room at night to confess her feelings, only for Fio to brush her off. Unable to take it anymore, Vivian’s emotions burst forth, and she was about to force a yuri romance on Fio.

No, no, no! That can’t be! Leon clutched at his hair, rejecting his own conclusion. Vivian had only met Fio for the first time today. There was no way her feelings could’ve developed this quickly!

Leon tried to calm himself down. He trusted his sister. He had to be misunderstanding what he’d seen.

And even if he was wrong about everything else, there was no reason Fio would accept a girl she’d only met that day and agree to her yuri advances—

“I understand, Vivian—promise—you—love!”

Fio, what are you saying?! Leon screamed inwardly.

From the words Leon could make out, Fio sounded overjoyed as she responded to Vivian, like a traveler in the dark who’d finally caught sight of the light.

Leon’s eyes grew bloodshot. He hadn’t expected the thing he feared most to happen so soon.

Before he could win Fio’s heart, the girl who mattered most to him had been stolen away by someone else—and that someone was his own sister, who mattered just as much to him!

How could anything be so completely unreasonable?

And yet a tiny sliver of hope remained in Leon’s heart. He stubbornly clung to the belief that he had to be misunderstanding things!

“I know—you feel—something more than ordinary—love.”

At Fio’s words, Vivian’s voice turned bashful. In the darkness, Leon could sense her heartbeat racing.

Leon’s heartbeat, meanwhile, began to slow. His eyes looked almost lifeless, drained of all light.

Haha, what… So Fio really does like Vivian. She even confessed. And Vivian reacted to Fio the same way I did…

Leon had never seen Vivian wear such a bashful expression. The only explanation he could think of was that she was in love—the same way he acted around Fio.

I guess we really are siblings. We even have the same taste, huh, little sis… Your big brother can’t exactly be happy that you’re in love with Fio too.

“—This is a forbidden love—”

The words Leon feared most slipped from Fio’s lips.

A forbidden love—wasn’t that exactly what Fio and Vivian had together? Who else could be in a relationship the world would never accept?

His little sister was a lesbian, and she’d fallen for a girl she’d met that very day. She even liked her enough to sneak into her room at night and confess.

Thinking back, Vivian had given Fio the affectionate nickname “Little Kitten” the very first time they met.

She must’ve fallen in love with Fio at first sight, just like he had.

And most importantly, Fio had accepted Vivian’s confession. Her feelings had been so fiery and intense that Vivian had fallen completely, turning into a bashful girl in love.

Thinking of how cold Fio had been toward him, and how differently she treated Vivian, Leon finally understood: he’d been rejected. The girl he secretly loved had chosen his little sister as her lover.

“B-but maybe… even if there’s only a one-in-a-million chance, I could just be misunderstanding things?”

As if to reassure himself, Leon whispered so softly it was almost inaudible. He decided to risk it and move closer to Fio’s room, even if he might be discovered. This time, he had to make sure he heard their conversation properly.

“Don’t tell my brother about this.”

“Of course, Vivian. This is a secret just between the two of us.”

Leon heard the clearest conversation he could’ve hoped for: Vivian and Fio’s promise to be together.

Only then did he understand. He was like a defendant dissatisfied with a court’s verdict, appealing all the way to the Supreme Court—only to receive a death sentence.

Later, Leon couldn’t even remember how he’d left the place and made it back to his room.

“I actually got cucked by my own little sister…”

No matter how clearly the facts were laid out before him, it still seemed too absurd to be true. In the end, Leon crawled under the covers and forced himself to sleep.

“I must’ve been so tired that I hallucinated. Or maybe I’m dreaming! There’s no way Fio and Vivian fell in love this quickly. When I wake up tomorrow, I’ll make sure to get to the bottom of this!”

In his heart, Leon still clung stubbornly to that last sliver of hope.