Mamahaha no Kokoroe

Misaki Yamazaki dies of illness—only to wake up reincarnated in the world of a manga she once read. To her horror, she’s reborn as the story’s cruel stepmother, notorious for abusing the young protagonist. Even worse, she regains her memories just one day before the wedding, leaving her no chance to escape her fate. Determined to change the story, Misaki resolves never to mistreat her new stepson. But when they finally meet… he’s unbelievably adorable! As she raises him using knowledge from her previous life, even her cold, distant husband begins to soften. For the sake of her stepson, she’s willing to use every advantage at her disposal. A unique parenting fantasy begins—changing another world’s child-rearing with the power of love and otaku knowledge! (Source: Alpha Manga)