Since the boba doodle looks like it's set in the bamboo forest after Lucky completes all side quests (Hence Momo being with her) I like to think that leaving the island and triggering the credits is non-canon and that Lucky lives out the rest of her life on Champion Island. Or, at least, she stays a while before leaving. This fanart shows Lucky and Momo going out to eat at the noodle shop in Tanooki city. Lucky grabs 2 of her 50 free bowls of noodles she earned by being the chosen one to have for the meal, and Momo uses a chopstick to cast a heart spell (Which does nothing physically since the cat ghost isn't on screen) Help I may be too invested in the lore Me when I try drawing noodles for the first time and it's peak: