The Black Gem's Secret
It's been a while since Nero sat so quietly on my lap like this. Though "quietly" might be an exaggeration—she's completely absorbed in fiddling with the ring using her front paws' jelly-like pads. Her cat form feels more familiar and reassuring to me, somehow putting me at ease. Not that I dislike her other forms; if anything, they have their own appeal. It's just that when we're indoors with a bed nearby, there's nowhere safe for my eyes to rest.
"Nyaang."
When I handed her the ring, I expected her to leap with joy, but instead she clutched it carefully with both hands, pressing it close to her chest as her eyes grew moist. The sight sent a jolt straight through my heart. Honestly, I'd braced myself for her to pounce on me right away like Harpy or the others, but ever since that wild night, both Scarlet and Nero have been noticeably more subdued. Instead, she padded over, wrapped her arms around my neck, and gave me a light kiss. Now she's been smiling nonstop while playing with the ring ever since.
"This place really is cozy."
Right beside me, Founder sat with her head resting on my shoulder. The reason Nero could demand me every night was because Founder had been giving us space. Come to think of it, there might have been some kind of agreement between them.
"Pet my head, big brother."
"Huh? Sure, anytime."
Her hair felt incredibly smooth and silky as I ran my fingers through it. It had been far too long. Nero perked both ears up immediately and nudged her head toward my hand, so I ended up using both hands at once. Good thing I had two arms.
"What did everyone say?"
"They all liked them. I love mine too."
The question was obviously about the rings, so I answered without hesitation. The rings Founder had given me. I hadn't expected something this beautiful, which was probably why I felt even more satisfied now.
"Ahem, of course. My dear little sister helped, after all."
"Your sister... Observer?"
She usually whipped things up in no time, but this time it had taken longer than usual. I hadn't expected Observer to be involved.
"Yep! She moved just enough that I didn't expect it, so this is her reward and praise combined."
"..."
What did "just enough that I didn't expect it" even mean? It reminded me of something. The day Harpia hatched from her egg, I was leaving Harpy's containment room with a grin when I ran into Observer. Or rather, she had clearly come to find me. Without any preamble, she demanded I make a choice about the future. She was also the one who told me to finish Undine's counseling quickly. After that came my disastrous first meetings with Scarlet and Dorothy...
Yet here I was, still able to laugh and chat with Harpy and the others. Even with all my mistakes, I must have met the minimum requirements of the future she had foreseen.
"...That's just my shy little sister rambling."
"Oh?"
"She said you did well. And she meant it."
Ah, I see. I'd nearly died several times recently. So much had happened. Even though it had only been a short while in reality, the time I'd spent inside Dorothy's memories felt so long that everything recent seemed distant.
"I don't have any talent for making pretty things. But what I'm bad at, my sister is good at."
"Even something like these gems..."
"Yeah. She did all the cutting into pretty shapes and engraving the patterns. She's meticulous, so she's good at that kind of thing. In exchange, I prepared this."
"This black gem?"
It was darker than the usual black I knew, yet when light hit it, the reflected glow was almost mystical. Definitely not an ordinary stone, though I still didn't know what kind of gem it was.
"That's right! I didn't just sit around doing nothing either. On the contrary, since my sister can't do it, I handled it."
"If you help each other, you can do anything, huh."
"Yep...! We're literally two halves of one whole."
They really were the ideal pair of sisters. So what exactly was this gem?
"Ah, that's a piece of my eyeball."
...Eyeball?
"...Your eyeball?"
"Nyaha...?"
I'd heard her clearly, yet Founder nodded so casually that I felt completely lost. Nero's reaction—nearly dropping the ring—confirmed I hadn't misheard. I stared straight into her pitch-black eyes, only to regret it immediately. Those eerie black pupils remained perfectly flawless.
"Yeah, it's not good to stare at my eyes for too long."
"Ah... um..."
I didn't know whether to apologize or say something else, so I just stood there flustered.
"Like I said, I gave them to the people who matter to me, right?"
"...Yes, that's correct."
Thankfully, Founder's question shifted the topic and gave me a moment to breathe. But the follow-up confirmation made cold sweat run down my back.
"My eyeball ring will definitely help someday, so try not to take it off your body if you can."
"..."
So it really was called the eyeball ring. Or maybe "my eyeball ring."
"So... by the way..."
"...?"
While I was nodding blankly, I noticed Founder fidgeting, pressing her index fingers together. Sensing my gaze, she hesitated before speaking.
"Um, I still haven't received one yet?"
"?"
Ah? Founder... ah? A ring...? There was exactly one left, actually.
"Ah, no. I mean, I definitely think of you as family, just as precious, but the meaning of the ring isn't quite..."
"Huh? Do I have to mate with you too, big brother?"
"Excuse me...?"
"I'm interested in the breeding activities you show, but I probably won't get pregnant..."
Interested...? What was she even...
"N-no no no, that's not it...!"
"But the common point among everyone who's received a ring so far is that they're all female, and they've all mated with you, right?"
"...That's true."
It was an undeniable fact, so I couldn't deny it. But how was I supposed to explain this?
"It is, but...! It is, but..."
Being intimate like that... whether you called it physical affection or something deeper, there was clearly a bond that grew stronger. Some might find it vulgar, but people—especially men and women—tended to grow closer in heart the closer their bodies became. And it was because our hearts had already grown close that we touched each other, not the other way around.
"Is that so?"
"Uwaa...?"
Suddenly, she grew into the form of an adult woman—the same one she'd shown only once before. She tucked her fallen bangs behind her ear with a playful glint in her eyes that left me utterly flustered. Last time she'd reverted to a child's form because I couldn't focus on petting her head. Now it felt deliberate, and that made it far more dangerous.
"Wait, wait a second. You didn't forget I'm here, did you?"
Nero instantly transformed into human form, as if her stray-cat detection sensor had gone off. She clung tightly to me and shot a wary glare at Founder. It was reassuring, but with her sitting on my lap like this, the close contact was making things... difficult in several places. If I didn't clarify things quickly, the atmosphere could take a very strange turn.
"Wearing the ring means... it's usually something shared between lovers rather than family."
"If you have a child, you become family, right...? Besides, she never takes the ring off."
She was talking about Harpy, wasn't she? Yeah, that made sense. Pretending not to know in front of her wouldn't be wise.
"You just don't want to give one to me?"
"That's absolutely not true...! You've helped me so much until now."
Beyond just the help, whenever I looked at her, she felt like a lively younger sister with a big age gap. I'd never actually had a little sister, but if I did, I imagined it would feel like this. Of course, part of it was also how she called me "big brother."
"It's not just because she looks young... ah."
Ah, right. Come to think of it, Founder really did have a younger sister. If I compared it to Observer so she could understand, maybe she'd get my awkward feelings.
"You love Observer, don't you?"
"Yeah...! I love my little sister so much!"
She nodded energetically in her grown form, and various parts of her moved along with it, nearly making my eyes shake too. I somehow managed to rein myself in and continued.
"Th-then... that doesn't mean you're driven by lust toward Observer or anything like that, right?"
If she answered "of course not," then I could say I felt the same way about Founder. But instead—
"No?"
"No...?"
"Yeah, my little sister is so adorable. Even when she acts like she knows everything, she actually doesn't know anything at all."
Why... not?
"I want to teach her everything one by one. Of course, if my sister doesn't want that, I won't do it."
"..."
"Not just lust—I even feel thirst and hunger. I can guarantee that I want my sister, love her, with every kind of affection and desire there is."
...Hmm. Hmm. I felt a sudden tension, wondering if I'd carelessly touched something I shouldn't have. Now I was even questioning whether insisting on the ring's meaning really mattered that much. Observer's constant attempts to avoid and flee from her bright, adorable older sister's love suddenly didn't seem like such an odd reaction after all.
"...Which finger should I put it on? The ring."