Shiro Buta Kizoku Desu Ga Zense No Kioku Ga Haeta Node Hiyoko Na Otōto Sodatemasu Manga May 2026

The protagonist, Regulus Fenrir Ainsworth , was once the reviled first son of a marquis family—overweight, arrogant, and stupid. After dying from overeating at a banquet, he reincarnates? No, he simply remembers : a previous life as Tanaka Kaito , a hardworking Japanese office worker who loved cooking, budgeting, and caring for his younger siblings.

Waking up at age 7, Regulus is horrified at the monster he was destined to become. More urgently, he finds his 4-year-old brother —a frail, silent boy nicknamed “Hiyoko” (chick) by servants for his yellow hair and trembling demeanor—locked in a dark storage room, bruised and forgotten by their cold noble parents. The protagonist, Regulus Fenrir Ainsworth , was once

Fantasy, Slice of Life, Reincarnation/Isekai, Family Drama, Comedy, Redemption Waking up at age 7, Regulus is horrified

But as Luciel begins to smile and speak more, their parents grow suspicious. The engagement to a cruel noble girl looms. And someone from Regulus’s original “bad future” timeline seems to have noticed the changes… The engagement to a cruel noble girl looms

Fans of Ascendance of a Bookworm , The Savior’s Book Café in Another World , My Next Life as a Villainess , and anyone who loves “found family” + “raising a child” plots with a realistic, heartfelt edge.

A deceptively gentle manga about the hardest kind of courage: changing yourself to save someone who has no reason to trust you. Highly recommended for readers who like their isekai low-fantasy, high-emotion, and heavy on the domestic fluff earned through pain.

Here’s a solid, detailed write-up for the manga: