Complex sentence: The chapters of the Claymore manga series are written and drawn by Norihiro Yagi and serialized by Shueisha, first in "Monthly Shōnen Jump" then in its replacement "Jump Square".
Split into simpler sentences: The chapters of the "Claymore" manga series are written and drawn by Norihiro Yagi. They began serialized by Shueisha, first in "Monthly Shōnen Jump" and are currently serialized in "Jump Square".