Different from others, Iroha quite respects Hachiman and is very fond of him. despite her way of keeping her image with others, she shows her true colors to Hachiman. Thus she feels lot more comfortable with him. She begins to admire him for his intelligent and presence of mind. She was deeply moved by his desire to have something genuine and inspired by it. She is always surprised by his concern for her which is shown by her reactions during Hachiman's offer to carry her bags. She always seems to rely on Hachiman from student council election to Christmas celebration in collaboration. When he refused to help her any further after that, she goes to the trouble of requesting Hiratsuka sensei for Hachiman's help as a student council order. She uniquely calls him "senpai". Due to the similarities of their personalities, Hachiman is especially wary of her, and mentally grants her a "third grade Hikigaya certificate" for her ability to understand how his mind works.