Segawa Izumi is the student representative for Hayate's class at Hakuō Academy. She is the younger fraternal twin sister of Kotetsu Segawa. She met Hayate when they were younger (volume 17 flashback) as she was getting attacked by a dog and gave him a kiss for saving her, as well as telling him she would be his bride when they're older; although she mentioned nothing about that incident when she first met Hayate at Hakuō Academy, possibly due to both parties not remembering each other. Like her friends, she addresses Hayate as "Hayata." Izumi gets along well with Hayate, and is comfortable enough to even change clothes while he is in the same room (though not for him to actually watch her change). Later on, she realises she may have started to develop feelings for Hayate.