In the anime/manga Kampfer, there are a lot of various characters.
Natsuru Senō (瀬能 ナツル, Senō Natsuru) is the series' main protagonist. Second year student of Seitetsu Gakuin High School, he has a crush on Kaede Sakura, one of the school beauties, to the point of single-mindedness and sees other girls with indifference.
He is chosen as a Blue Kämpfer by Moderator and set up as a Zauber type with power based on fire. In keeping with the rule that all Kämpfers are females, he turns into a girl upon transformation.
After a fight with Shizuku Sangō exposed his Kämpfer form to other students of the school, Shizuku arranged to have him enrolled in the girls' class to fulfill public curiosity in a way that diverts attentions away from Kämpfer battles. His Kämpfer form has subsequently been ranked among the Three Beauties of Seitetsu (the other two being Sakura and Shizuku) and, much to his own dismay, become subject of intense affections from Kaede (who has displayed no particular interest in his Normal form) and the female student body.
Akane Mishima (美嶋 紅音, Mishima Akane) is the school librarian and Natsuru Senō's friend. She is also a Blue Kämpfer like Natsuru.
Normally very shy (which might very well be attributed to her tendency of misunderstanding what others are trying to do in a borderline-erotic way) and soft-spoken, she becomes foul-mouthed, bitter, vindictive, and trigger-happy upon transforming into a Kämpfer.
She explained most of the rules of being a Kämpfer when Natsuru's own Messenger gave no such details. She is a Gewehr-type Kämpfer who uses an 1911 .45 pistol and appears to be ambidextrous.
In addition to having Natsuru as the first male to establish in-depth friendship with her, Akane eventually begins to harbor feelings for him, becoming jealous and easily irritable when he talks about another girl (most if not all of the time being Kaede Sakura) in front of her or when another girl takes an interest in him (whether that interest is romantic in nature or not).
Despite often responding with indifference, however, Natsuru does later tell her that if Kaede were never on his mind, she (Normal form) would have been the kind of girl he "sees no problem with".
Shizuku Sangō [三郷 雫, Sangō Shizuku] President of the Student Council and one of the Three Beauties of Seitetsu who is a model student with a perfect attendance record.
In addition, however, she is also a Red Kämpfer fighting with the Schwert ability of wielding two chained daggers at will. She wants to expose the Moderator's intentions and would not fight Blue Kämpfers until that goal was accomplished.
After being spared following a defeat by Natsuru Senō, she enters a truce with Natsuru and Akane Mishima and has since taken an interest in Natsuru in a slightly sly and teasing manner, throwing him off balance with embarrassing remarks/actions while maintaining a poker face in the process, despite being constantly treated with suspicion as a result.
However, after being invited by Kaede Sakura to visit her home and then spend the night there, Shizuku is seen getting inquisitive about what happens after Kaede has sneaked into Natsuru's bed and then wondering if she is indeed feeling jealous over Kaede getting the chance to do so. Later on she continues to give off hints that she is romantically interested in him, asking him out on a date and eventually deep-kissing him in front of Sakura and the others although her constant ambiguity again seems to become her undoing (a fact she seems to have realized, calling her love an unrequited one), as Natsuru keeps thinking that she is trying to lower his defenses whenever she makes an advance on him.
Mikoto Kondo (近堂 水琴, Kondō Mikoto) is Natsuru Senō's childhood friend who only recently reunited with him due to her father being an archaeologist who lives abroad, a way of live that already made her think little of doing things others would consider far too dangerous.
Although having too much pride to explicitly admit, she has feelings for Natsuru and is more than a bit bothered by the presence of a girl with the same name as his (who in reality is Natsuru in his Kämpfer form).
Even after the misunderstanding is later cleared up, the advances made by Akane Mishima and Shizuku Sangō on Natsuru (Mikoto apparently does not believe Kaede Sakura would reciprocate his feelings) subsequently makes her even more nervous about her chance with him as well. When she was seeing Miss Seitetsu contest of the school festival, she caught a bouquet that Kaede tossed with a Messenger hidden in it, consequently being turned into a Schwert-type Red Kämpfer armed with a katana.
Her love for curry is to the point of cooking and consuming it for every meal, usually making it for Natsuru.