Story
"Why should it matter how old you are if you want to start something new?" The strongest guy around, who also happens to be middle-aged, strives to be an adventurer! Everyone seems to think you should pursue your dreams while you're still young, but there's one man who just can't give up. In a world where most people who become adventurers do so in their teens, a guild employee in his thirties, Rick Gladiator, seeks to become an adventurer instead.
Synopsis via AniList (English).