Sena Kashiwazaki

Sena Kashiwazaki is the female tritagonist of the Boku wa Tomodachi ga Sukunai series. She is the first recruited member of the Neighbor's Club and the daughter of Tenma Kashiwazaki, headmaster of St. Chronica's Academy. Her wealth, beauty, and outstanding academic and athletic performance have made her popular among male students, and likewise, have made her an outcast among girls. Starting from high school, Sena continuously took first place in all tests, exams, and competitions. A year prior to the start of the story, Sena in her freshman year of high school, won multiple athletic events in the school annual festival. She entered the 200-meter race, cavalry battle, the scavenger hunt race, the obstacle race, the bread-eating race, the marathon, winning all of them effortlessly.

Before joining the Neighbor's Club, Sena didn't have any female friends, because she is envied by other girls, due to her good looks and popularity with the opposite sex. Despite being constantly surrounded by boys (who, according to her, are "doormats"), all she wants are true friends, which drove her to join the Neighbor's Club. Sena shows a dislike of all things "ordinary."

On the outside, Sena appears to be an ordinary high school girl, but in truth, Sena is arrogant and prideful by nature and she is well aware of this. Sena considers herself to be the school queen or goddess and so often she treats her male classmates only as servants to be used, although many of them would like to be her boyfriend. Nonetheless, she holds Kodaka to a higher standard. Sena also believes that there are two types of girls; the ones who are willing to be her friends and the others who are not worthy of her. Sena also does not treat the boys in her class with much respect due to them constantly ogling her, and slavishly doing whatever she tells them to. However, whenever Sena's ego is shaken by someone (usually Yozora), she bursts into tears and flings childish insults before running away. Sena was surprised to see that Kodaka does not act like the boys in her class (wanting to be stepped on) and hence, views Kodaka in a different light. She first saw him in this different light when he rescued her from some guys who were harassing her at a public pool. Since then, her feelings have increased to the point where she nonchalantly admits that she wouldn't mind marrying him and that she is in love with him. Her father was the best friend of Hayato Hasegawa, and because of this, some time in her early childhood Sena met Kodaka Hasegawa (though both of them couldn't remember this).

Sena enjoys playing video games—including dating sims and eroge—partially because they allow her to make female (if virtual) friends. She is a perfectionist by default. Sena always tries her best at everything and is willing to go to great lengths to do something perfectly (once playing a video game without sleeping until she had finished it). Sena gets so involved in her games that she becomes very angry if they are insulted in any way. She becomes extremely engrossed in things she is interested in, sometimes to beyond reasonable levels (as seen with her grudge against Yozora), while completely ignoring things she is not interested in. She possesses both the confidence and the means to pursue whatever she may desire. Sena is very gullible and often fails to see through the tricks Rika and Yozora play on her, even when the resulting humiliation is plain to see, (an example being the "heap" hairstyle). She only realizes her mistake when her father or some other person points it out to her. Yozora calls her "Meat" (Niku) an insulting nickname which she secretly likes because it is the first she has ever received. Her father is a friend of Kodaka's father, and pulled strings so that Kodaka could attend St. Chronica's.

Despite her princess-like arrogance, it's been shown that Sena genuinely cares for the other members of the club.

In Volume 7 of the Light Novel,

In Volume 8,

In Volume 9,