Transmigrate inside a Web Novel as a Side Character. - Chapter 14 - Reunion.

Four years ago, after a night of drunkenness, she had a relationship with a stranger and fled in panic upon waking up. Four years later, she returns with a soft, cute little bun by her side.“Bad uncle, you're not allowed to bully my mommy!”The man looked at the little bun, who was not even tall enough to reach his waist, and gave a charming smile. “Shouldn't you ask your mommy why you look exactly like me?”

Akira Kisaragi traverses into the Bleach world, unlocking a check-in system.He initially thought that by checking in daily, he could become stronger, soon become the Captain-Commander, join Division Zero, punch Yhwach, kick the Soul King, and marry Unohana...However, the system's style wasn't quite what he had imagined.〈 Check-in complete, obtained Genryūsai Yamamoto's secret roasted sweet potato! 〉〈 Check-in complete, obtained exclusive attribute: King of Normal Attacks, effect... 〉〈 Check-in complete, obtained Retsu Unohana's... 〉Akira's eyes suddenly lit up!“Seems like this might not be so bad after all!”

“A cheat system? Do you take me for a fool? Nowadays, where can you find such a good thing falling into your lap? Scram from my head. Is this is new kind of fraud? Or is this a murderer training system of aliens that contains the ability of hypnotism?”

“No, I am the chaos that whispers from nothingness, the nightmare of all living beings in the Southern Ten Stars, the successor of the unparalleled God and… your elder sister.”

“…I only have a younger sister, I don’t have an elder sister!”

“No, you have one. I am an illegitimate daughter. It’s just that your dad didn’t inform you.”

- Description from Novelupdates

Fate, a gatekeeper who had been working for the castle, is beset by a few burdens.