Poww is the 32nd Arrancar in Aizen's forces and one of Barragan Luisenbarn's six Fracción. He's arguably the tallest character in the entire series—a genuinely massive guy who dwarfs even Sajin Komamura, already one of the biggest Shinigami around. His mask fragments are pretty distinctive: a large plate across his chin with two horn-like protrusions, plus a pair of green triangular markings beneath his eyes that have circles in them. He sports a monkish hairstyle and wears a customized Arrancar uniform styled like Chinese garments with long sleeves that really emphasize his oversized hands. Standard hakama, martial arts-style sandals like Ggio Vega's.
Personality-wise, Poww is quiet and thoughtful despite the intimidating physique—calm and serious, doesn't say much. But he's got a mean streak of arrogance that comes out when he's fighting. He'll trash-talk opponents about their looks, mocking Ikkaku's baldness or taking shots at Komamura for being, well, a dog. Still, he respects the hell out of Barragan, basically treating him like a god and praying before he fights.
Content compiled by AnimeList.moe from publicly available sources.