Izumi Yuuka is the president of the gardening club and the only member aside from Kenichi. Izumi is a young teenage girl of average height with long black hair she has in two braids in the back with some fringe in the front. She is typically seen in her school uniform at school or her swimsuit at school and is always seen with her glasses on.

She is a shy girl who harbors a crush on Kenichi, though he is oblivious to it. Her attempts to ask Kenichi on a date are always interrupted. She is relatively a friendly and kind hearted young girl that is also polite and rather shy, especially when it comes to Kenichi. She heard of the rumors about him, but after getting to know him, she knew they were wrong and accepts him for who he is. Her feelings eventually develop to love, though Kenichi doesn't share the same feelings. Despite this, he cares for her very much as a friend and is always kind to her and worries over her well-being, such as being enraged when Daimonji used her as a hostage and was determined to save her.

In Ryozanpaku, she is jealous of Miu because Izumi is in love with Kenichi, so she joined in on the plan Niijima created. She's also a little jealous of Miu's figure and how well-endowed it is compared to others and herself, wondering how she has such a figure for someone so young. Despite this, she and Miu are good friends and she cares about her just as much as Miu does to her. Though she seems to be aware of Kenichi's feelings and relationship with Miu, she respects him enough to choose who he wants to be with, but that doesn't stop her from trying to win his affection.