Who is Karel from The Book of Laughter and Forgetting and what is their importance?

Karel is Marketa's husband, he is tired of his relationship with his wife, despite his love for her. Both Karel and Marketa love one another, but Karel longs for freedom and an escape from his life where everything is programmed and controlled, based on his past actions. He is a woman chaser and frequently has relationships with other women, which Marketa is aware of. For this reason, he is permanently made to feel guilty in his relationship with Marketa.