Natsu Dragneel and Gray Fullbuster come from the anime Fairy Tail. Both men have always had quite a friendly rivalry competing over everything and trying to one upt he other constantly, both have pretty large appetites which often make them turn into eating contest to solve their disputes despite ending usually in a tie with both stuffed to the brim but refusing to accept defeat. They are known to be massive gluttons who stuff themselves like crazy trying to one up the other.