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

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

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

Using his past-life knowledge, Regulus makes a solemn vow: He’ll lose the “white pig” weight through proper nutrition and exercise, outmaneuver the scheming adults who want him dead, and—most importantly—raise Luciel into a strong, kind, and confident young man. From cooking homemade meals and teaching basic math to confronting abusive tutors and planting secret vegetable gardens, Regulus builds a quiet revolution inside the gilded cage of nobility. From cooking homemade meals and teaching basic math

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. A selfish, despised noble known as the “White

A selfish, despised noble known as the “White Pig” for his gluttony and cruelty dies in disgrace—only to wake up as a child again, memories of a past life flooding back. Now armed with the wisdom of a former modern-day Japanese citizen, he must raise his timid, neglected younger brother from a life of abuse and prepare him for a future where their family’s ruin is all but certain.