To determine the two topics that interact to create a theme for the overall story, I would need more context about the specific story. However, based on the typical themes often explored in literature, "guilt and gloominess" often interact to create a deep and reflective theme regarding the consequences of one's actions and emotional turmoil.
If you provide specific details or a summary of the story, I can give a more accurate answer. Otherwise, based on the options given, "guilt and gloominess" appears to be a strong pairing for developing a central theme.