Seraphim is a Bystander

Shin Futaba Household
 
On the night Aoi returned from his school trip, the entire Futaba family was gathered around the dinner table. Even his father, who was usually late getting home, had left work early and made it back in time.

Each person looked a little different, but they all shared the same restless energy, fidgeting in their own ways. The first to speak was Aoi’s father.
“Well… I’ve got plenty I’d like to ask, but first of all—I’m just glad you made it home safely.”
His expression was unusually tense, but even as he spoke, his eyes kept flicking toward Aoi’s shoulder.

“Yeah, I’m home, Dad. And the one sitting on my shoulder is the one I messaged you about…”
“Right, her name was Yuzu, if I remember correctly… So?”
“Let me explain everything from the beginning.”

As they ate the dinner Mom had prepared, Aoi started from the top—how he'd encountered a divine residence during the trip. The more he spoke, the more complicated his father’s expression became.
“I see… If someone close to the gods believes it’s best for that cat to stay by your side, then the Futaba family has no intention of going against their wishes.”
“So—!”

“Yeah, just make sure you take proper care of her, alright?”
“Thanks!”
Relieved by his father's response, Aoi smiled as he gently stroked Yuzu, who was curled up on his lap. With his good looks and her adorable appearance, the two made a picturesque pair.

“...!?”
I had been quietly reading while listening to the family conversation, but suddenly slammed my book shut when a wave of dread coursed through me.
What was that!?
Nothing showed up in my detection range. The ones I’d been monitoring shouldn’t be moving yet either…

Without breaking any restrictions, I activated every bit of my seraphic capabilities to scan for external threats, but no matter how I sliced it, there was nothing around that could endanger Aoi and his family right now.
What the heck is this feeling...? The last time I felt something this ominous was the morning that damned Creator God dumped a new pile of work on me…!
“Also… there’s one more thing I want to tell everyone.”
Oblivious to my rising tension, Aoi continued speaking to his family, looking far too cheerful.

As intuitive as he is, especially when it comes to ignoring logic or reason, if Aoi seems this at ease, then maybe—just maybe—there really isn’t any immediate danger.
...Unless the Creator’s cooking up something unnecessary again from the divine realm.
“Actually, it turns out… I had another family member inside me all along.”

“Huh?” “Oh?” “?” “Woof...?”
“…Excuse me?”
My thoughts ground to a halt. Completely.
Ahhh… so this is what it feels like to short-circuit mentally. I guess my human-side brain is still kicking around, huh…

It was like taking a direct hit from a supernova for skipping work. Even as my logic scrambled to recover, my emotions just sort of… sat there thinking dumb thoughts.
“I know it sounds unbelievable, so maybe it’s faster to just show you! Seras, would you mind coming out?”
While I was still rebooting internally, Aoi called out to me—looking way too excited about it.

“Wait—Aoi!? What are you saying!? Didn’t we agree not to bring me up!?”
“No secrets from family, remember? You’re family too, Seras. I’m not hiding anything.”
“No no no, now’s your chance! Just laugh it off like ‘Haha, just kidding~!’ or something!”

“Not happening! If I said that now, I’d just sound completely nuts!”
Even as we argued—well, I was mentally yelling and he was speaking aloud—his family just stared at him with their mouths half open.
Ugh… I completely failed to predict this. Haven’t slipped up like this in a long time...

Everyone other than Aoi has thoughts and emotions that I can interpret logically. But Aoi’s feelings and thoughts come straight into my mind. That’s why it’s so hard to predict when he acts purely on instinct.
Now that I think about it… this possibility was always there from the start, huh.
“Come on! Say ✧ NоvеIight ✧ (Original source) hi and talk to everyone!”

Even as I tried to understand why I missed this, Aoi cheerfully insisted I switch with him.
So that bad feeling was this. No getting out of it now...
I closed the book I had been holding, shoved it back into the shelf, and resigned myself to the switch. When I opened my eyes, Aoi’s parents were staring in stunned silence, mouths wide open. And Ritsuki—he looked positively delighted.

“Uh… good evening. I’m Seras, the one Aoi was talking about.”
““Ah—uh… Good evening?”” “Hi there!”
While his parents remained dumbfounded, Ritsuki practically skipped over, smiling in a way even I could visibly recognize.

“Ah, Ritsuki—”
“Big brother turned into a big sister!”
“Guh—!”

Big sister… Well, he’s not wrong. This body is definitely female.
And so, I—Seras, former high-ranking seraph—was brought to my knees for the first time since reincarnating into this world.