Kirika is the leader of the eiken club she is a purple haired amazon with 99cm Gcup breasts at the start of the series.
She is the one that forced Densuke Mifune to join the Eiken club because according to her he had no skill or talent and has tormented him oftensince, Often using her breasts to tease him through either smothering, hitting or just deliberatly giving him a peek. She was little to no inhibition's, hardly ever wearing underwear unless bottom's as part of a swinsuit and always wearing the minimal necessary to stay decent. She also has no problem with groping Chiharu Shinonome which she often does to tease Densuke.
It is possible that Kirika might like Densuke although this is very rarely scene and might just be teasing. Considering that almost every main or secondary girl in the series likes him then it's not to unbelieveable she might as well.