Complex sentence: Mikey Kudo, in Japan, is the primary human protagonist in the manga and the first season of the anime (episodes 1-54), an upbeat 7th grade boy who helps anyone in need.
Split into simpler sentences: Mikey Kudo, known as in Japan, is the primary human protagonist in the manga and the first season of the anime (episodes 1-54). He is introduced in the series as an upbeat 7th grade boy who helps anyone in need.