Complex sentence: Because of their optimistic personalities, Kafuka and Maria get along quite well and Chiri takes it upon herself to watch over Maria after being touched by her unwavering optimism and love for Japan.
Split into simpler sentences: Because of their optimistic personalities, Kafuka and Maria get along quite well. After spending some time with her, Chiri takes it upon herself to watch over Maria after being touched by her unwavering optimism and love for Japan.