Meguri is a third year student and the president of S�bu High School's student council. Although she is not a reliable leader herself, her personality has brought her immense support from the councilors and thus she is able to unite the student council. (Source: Wikipedia)
Haruno is Yukino's elder sister who is even more outstanding than Yukino. However, unlike Yukino, she shows a good attitude towards other people, even if she has to lie about her true feelings most of the time.
One of Minami Sagami's best friends.
Saki's younger brother who requested the group's help as to find out about his sister's nightly activities. Which he later found out that her sister is working as a bar tender under a false name and age to support his cram school tuition. (Source: ANN)
Saika is a member of the tennis club who has a feminine appearance, but prefers others to not mistake his gender. He is called "The Prince" by his female classmates. On their first meeting, Saika asks help from Hachiman to join the tennis club, which was brushed off by Yukino. Saika then asked the service club to help him improve his tennis skills. He eventually became one of the few people in class 2F who would talk to Hachiman, and often hangs out with Hachiman.
Atsugi is a physical education teacher in S�bu High School. (Source: Wikipedia)
Shizuka is Hachiman's language teacher who also serves as his futures advisor/counselor. She is aware of Hachiman's supposed "problems," and takes steps to ensure he is freed from them, her first move being to force him into joining the Service Club. However, she appears to have some quirks of her own: she is a young smoker, she is very sensitive about her age, and she is often prone to quoting or copying scenes from popular shounen manga. She also never remembers to knock before entering the Service Club's classroom, much to Yukino's chagrin. (Source: Vistrans)