In her civilian attire, Kazuho looks like a timid and shy young girl with big poofy pink hair and glasses. Her hair is a tad messy and her eyes are concealed by the glare of her glasses.
When she wants to use her quirk and express herself, she paints a black mask, ties her hair in pig-tails, dresses in a succubus themed one-piece black leotard with a heart-shaped opening in the center of the chest, a super-miniskirt with three hearts on the belt, knee-high boots, and elbow length gloves.
Pop☆Step is a very logical and intellectual person; as she acts as the brains of the vigilantes. She has a habit of berating both Koichi and Knuckleduster when either of them acts up in a way that she disapproves of. She also constantly denies having any involvement with them to the police, even though she clearly does.
Koichi notes that she has difficulty apologizing, likening her to a child. She appears to act like a more moderate Tsundere, mocking and insulting her allies despite clearly caring for Koichi. Despite this, she will still mock him for his attitudes and resignation to his situation, which she feels guilt for. Otherwise, particularly with Knuckleduster, she can be confrontational, and somewhat aggressive and territorial towards him. As an Idol, she appears to love singing and performing, despite not being particularly skilled or talented in either. She does her performances with lots of enthusiasm and seems to take pride in her appearance when she performs. This vanity seems to extend to her looks at all times, including when she is not dressed up. She once told Koichi that if he called her civilian attire plain, she would kill him.
She feels guilt and is genuinely apologetic towards Koichi for an incident in the past, which resulted in her being saved by him, though at the cost of him missing an examination to attend a Hero High School, thus ending his dreams of becoming a Hero. While she wants to thank him and apologize to him for saving her, she seems unable to do this easily, particularly around other people.
When she was younger, Kazuho tried to leap across a river but the ground was wet from rain, so she slipped and fell into the river. On his way to take his hero-course entrance exam, Koichi Haimawari pulled her out of the water and gave her his silver age All Might hoodie.
The two met when Koichi tipped Kazuho off about the police arriving for her. She thanked him for his help and the two became friends and fellow Vigilantes. While she does not partake in the Vigilante missions as actively as Koichi, she still supports him during the missions through other means besides combat related. As they are both Vigilantes, Kazuho trusts Koichi enough to reveal her public image.
Though they are friends with one another, the two have bickered over disagreements regarding Koichi's path as an illegal hero. Nonetheless, she still supports him.
It is revealed that Kazuho and Koichi met before when they were younger. Kazuho had fallen in the river and could not swim despite the shallow water. Koichi jumped in to rescue her and immediately left when he was running late. Koichi appears to not remember Kazuho from this encounter due to the limited interaction between them back then. However, Kazuho remembers Koichi because of the jacket he gave her after being rescued. She kept that jacket as a remembrance of that moment. She also apparently has been watching Koichi from a distance before they properly met one another.
Kazuho appears to have a crush on Koichi while Koichi doesn't appear to reciprocate and is oblivious to her affection. Despite this, he treats her as a valued friend.
The two are fellow Vigilantes, but their relationship can be deemed as a rocky one as both tend to bicker with one another on more than one occasion. Kazuho does not appear to tolerate Knuckleduster's aggressive and violent attitude, especially when it gets out of hand. Despite that, the two are capable of working together during Vigilante missions.
- Kazuho's given name contains the kanji for kazu "和"(lit.harmony,peace,soften) and ho "歩"(lit.walk,a step). Her surname contains the kanji for Ha "羽"(lit.feathers), ne "根"(lit.a root,the source,the root), and yama "山"(lit. mountain).
- Kazuho's favorite food is yogurt.