Task: Question Answering
Input (English): Context: This time Rikki keeps her hand clamped tight over the struggling boy 's mouth for a good two minutes before she lets him go . He looks up at her afterwards , breathing hard to catch his breath , with a frank look of wary fascination on his face . And down and back around toward the shops walks Rikki . Here now on a street corner Rikki runs across several of her old buds , classmates from their days together at Casimir Pulaski High . " Hey Rikki !. 
Question: What may have caused Rikki to put her hand over the boy 's mouth ?
Output (English): She was showing her dominance .