Shirobuta Kizoku desu ga Zense no Kioku ga Haeta node Hiyoko na Otouto Sodatemasu summary:
A different world where Western and Chinese cultures are mixed. The only son of the Kikunoi empire, the swallowtail butterfly, who was born in that corner, was five years old. In addition to a fat figure, there are no allies. Moreover, it seems that his younger brother, Regulus, who suddenly appeared, will be killed over the right to succeed to the title in the future .... The only weapon is the memory of the previous life as a Japanese who suddenly grew up, "cooking and sewing". Meanwhile, the swallowtail butterfly was supposed to raise his younger brother, but- "My younger brother is super cute, isn't he?" ?? For his chick brother, he handmade educational toys and developed chawanmushi. By mobilizing all the special skills and housework power of the previous life, even rough territories are steadily improved! A fantasy of territorial management of young brothers, where a small step involves the gods and transforms them into a country!