Tabenai no? Ookami san
Tarou was left in the forest as a child as a sacrifice for the wolfman, Ul. Ul says he's way too small to be a sacrifice, so he ends up raising Tarou, assuring him that he'll eat him one day, while really, he waits for Tarou to become big and strong enough to run away and live on his own. They're very cute, and Tarou is such a sweetheart, though obviously they're going for a romance between these two despite that guardian/child relationship. Trigger warning: incest themes (guardian)
Sayonara Alpha
Chika has always believed he was an alpha, as demonstrated by his perfect record in school, sports, and his spot as the class president, until he met his fated pair, a seven-year-old boy named Haruka. Although this completely shatters Chika's perceptions of himself, and although his sexual urges threaten to run wild whenever Haruka is near, Chika can't stay away from Haruka, even if it means abusing his suppressants to give them more time together. This story is not for everyone since it has a teenage lead in love with an elementary schooler, but I honestly think it's an interesting take on the omegaverse and the idea of fated pairs and was overall handled well. Trigger warning: kissing/touching a minor, shotacon.
Puchi Puri