Tsuyu Asui/Relationships

Habuko Mongoose
Habuko was a student who attended the same middle school as Tsuyu and was the first friend Tsuyu made. They had many similarities to each other; having strange appearances that made it difficult for them to make friends and they were lonely individuals as a result. Often, Habuko would stalk Tsuyu but not with ill-intent. Tsuyu did not mind this because she understood Habuko's loneliness resulting from her appearance. Eventually, Tsuyu asked to be friends with Habuko. Touched by her kindness, Habuko agreed to be friends with her. They graduated from middle school together, but went to different high schools. Even though they are at different high schools, Tsuyu and Habuko never stopped being friends with one another as shown when Habuko sent her a message and Tsuyu herself notes that Habuko will always be her friend; their friendship became a catalyst that helped them socialize more and make new friends from their respective high schools.

Izuku Midoriya
Tsuyu respects Izuku for his heroic actions as well as his victory against Katsuki. During the Rescue Trial Arc, she was receptive of Izuku's plan to subdue the swimming villains, showing not only respect, but also trust. Tsuyu went to see how Izuku was doing after his battle with Shoto.

Interestingly, Tsuyu repeatedly tells Izuku to call her "Tsuyu" rather early on in their knowing of each other. He appeared to be the first person she was fine calling her by her first name, repeatedly reminding him to call her that every time he forgets. Considering Tsuyu has gone on to say she only wants people she considers, or wants to be a friend to call her that, it is clear that Tsuyu views Izuku as such. While Izuku seems to call her "Asui" more often than not, due to his polite personality, he has called her Tsuyu on occasion, and shown concern for her, showing he views Tsuyu in the same light.

Minoru Mineta
Tsuyu is frequently seen together with Minoru, although she constantly punishes him for perverted behavior or insensitive comments. Tsuyu most often hits Minoru with her tongue. However, the two seem to be on friendly terms, to a degree.

Ochaco Uraraka
Tsuyu and Ochaco appear to be great friends, as they are on a first name basis with each other. During the School Trip Arc, Tsuyu comforts Ochaco by offering to hold her hand, which Ochaco accepts. They fought well together against Himiko Toga and Ochaco was concerned for her after Tsuyu was attacked.

Mina Ashido
The two girls are friends, as they are often seen talking to each other. Tsuyu congratulated Mina for making it to the tournament even though she was angry about her own failure.

Fumikage Tokoyami
Although their interactions in the classroom have been minimal, Tsuyu has been paired with Fumikage a number of times. They worked together during the battle trial and the practical section of their final exams.

Tsuyu and Fumikage agreed to strategize prior to their practical exam, showing they had strong communication with one another. During their test against Ectoplasm, Fumikage and Tsuyu displayed elite synergy and teamwork. Their Quirks work very well together in both evasive and combat situations. Tsuyu provided support while Fumikage did the bulk of the fighting. Although they were overwhelmed by Ectoplasm, Tsuyu believed they would be fine because Fumikage is strong. Together they managed to pass their finals.

Nejire Hado
Nejire helped Ochaco and Tsuyu get an internship with Ryukyu. The three established a friendship with each other since Ochaco and Tsuyu listened and cooperated with Nejire splendidly during their internship, as well as when Ochaco and Tsuyu fought against Himiko Toga.

Sirius
Tsuyu and Sirius get along very well and they trained alongside in the internship. Sirius taught Tsuyu the importance of becoming a hero and agreed that she will become a great hero one day.

Himiko Toga
Tsuyu and Himiko are enemies. Tsuyu greatly dislikes Himiko for attacking her and Ochaco and considers her to be crazy. Despite Himiko's attempts to befriend her, Tsuyu reacted with displeasure, especially when Himiko called her by her first name, since that's something only her friends are allowed to do.