Rurouni Kenshin and Samurai X, is a Japanese manga series written and illustrated by Nobuhiro Watsuki. The fictional setting takes place during the early Meiji period in Japan. The story is about a fictional assassin named Himura Kenshin, from the Bakumatsu who becomes a wanderer to protect the people...

Yin and Yang is a balanced concept that describe how seemingly disjunct or opposing forces are interconnected and interdependent in the natural world, giving rise to each other in turn. by wikipedia.org