Main article: Ayuzawa Suzuna Misaki's rather eccentric and apathetic sister. She is very passive and shows very little emotion. She is in middle school so she is unable to take a part-time job. Therefore, to help her mother and sister in terms of financial problems, she joins magazine contests and always tends to win food prizes. She also keeps tabs on shops that are about to have sales on certain items so they could buy it in a cheaper price. Unlike her sister, Suzuna also excels in cooking because Misaki was always working, which leaves Suzuna with making meals. She learnt some tips from their dad, Sakuya, who is a highly skilled chef.

In the manga, Suzuna goes to Seika High (as a student) and is favoured over Misaki among the boys. She is comfortable with Misaki and Usui and calls Usui "ones-chan's wife".