|Manga Debut||Chapter 3|
|Anime Debut||Episode 2|
|Japanese Seiyuu||Ryoko Shiraishi|
|English Seiyuu||Maggie Flecknoe|
Kanako Sumiyoshi is one of Junpei's classmates and his childhood friend.
During elementary school, the two became enemies due to a misunderstanding where Kanako thought that Junpei was giving away her gift to another girl while in fact he was showing it to her. Due to her unhappiness from being at odds with Junpei, she takes on a Manba appearance at first, but dresses normally after returning to friendly terms with him.
Kanako is often seen bickering with Junpei and has a short-temper. She has a well-endowed body, and isn't afraid to flaunt it, but often gets unwanted attention and teased from Ichinose's hands. She still harbors feelings for Junpei.
She is a quick-tempered, confident, forthright and outspoken person. She harbours romantic feelings for her friend Junpei yet is afraid to admit this to him, seeing that he has a crush on Kaede.
She thinks of the other girls as obstacles standing in the way of his love. She gets angry easily and she seems to not be on good terms with Nagi because they fight in the pool over her touching her chest. She is a good friend of Mizuno's and always feels guilty whenever she spends time Junpei due to the fact that Mizuno has a crush on Junpei.
Junpei Kosaka: He has been her long time crush however due to a misunderstanding of a doll incident; they have been at enemies for a long time. Due to her mamba appearance Junpei never really saw his old friend in her however when her makeup is gone she goes about trying to take him along wherever she goes. She also gets jealous of him when he is with Mizuno and tries to get him away from her. She also wants to be with him however, his feelings are mostly directed at Mizuno instead of her. She knows this and tries through the series to get him to love her.
Kaede Mizuno : Mizuno is a good friend of Kanako and they support each other. Mizuno also gets the wrong idea when Kanako is with Junpei thinking that they are both girlfriend and boyfriend. Whenever Kanako is alone with Junpei she feels that she is betraying Mizuno because she is trying to take her love from her. They still remain friends through this and Mizuno even asks her for advice every once and a while. They do not want to stop being friends and they trust each other.
Akari Kirishima : Kanako only thinks of her as an obstacle in her way of Junpei.
Kotone Kirishima : Kanako only thinks of her as an obstacle in her way of Junpei.
Nagi Ichinose : Nagi and Kanako do not get along. Nagi admires Kanako's breasts a little too much, which sets Kanako in a rage against her, leading up to some awkward moments. They are at odds with each other because at times Nagi tries to prevent Kanako from getting close to Junpei while he is with Mizuno.
Chizuru Mochizuki : Kanako does not know who this person is and only sees her with Junpei at the mall. She calls him a jerk before he runs away with Chizuru.