Isidro is a young, spirited thief and aspiring swordsman who joins Guts' traveling party in the manga and anime series Berserk. Driven by dreams of becoming a legendary warrior, Isidro often finds himself in over his head but demonstrates courage, quick thinking, and a relentless desire to prove his worth. His youthful optimism and comic relief contrast with the darker tone of the series, and over time, he matures significantly, learning from his companions and growing as a fighter.