Tensei shitakedo 0 reberu ~ chīto ga moraenakatta chibi-kko wa, soredemo ganbarimasu ~ (Associated Names)

On his fourth birthday, Rudine, a boy living in a small village, regained memories of his past life. However, only his memories returned, with no fusion or even any influence on his personality occurring whatsoever. Despite thinking he might have cheat abilities from his biased knowledge of his past life, he found nothing. To make…