Sekijiro Kan/Relationships

Eraser Head
They are both Pro Heroes and homeroom teachers of the Department of Heroes for their respective classes. They have a good relationship but because Sekijiro views Class 1-A as rival of his Class 1-B, this rivalry is extended toward Shota, with Sekijiro acting out competitively towards him. Shota, for his part, doesn't care too much about this rivalry, and he even admits that Sekijiro is probably a better teacher than him.

Despite this rivalry, Sekijiro knows when to cooperate with Shota during serious moments. This was shown in their meeting with the media where he was worried that Shota would lose his temper though was surprised when the latter kept calm and agreed with the heckling.

All Might
While the two have not interacted with one another a lot, Sekijiro respects All Might, and like the rest of the U.A. Staff, he knows about his true form.

After All Might defeated All For One, losing his Quirk in the process and being forced to retire as a hero, Vlad thanks him for all the good he has done and voiced his regret for not acknowledging the large burden that All Might had to shoulder until it was too late.

Hound Dog
Sekijiro is a close friend of the U.A. Lifestyle Guidance Counselor, being one of few people who can understand him when he is unable to speak properly when angry.

After Hound Dog has an angry fit during the opening ceremony, Sekijiro approaches him and takes over for his speech, having understood what he wanted to say, and interprets Hound Dog's words to the students.

Class 1-B
Vlad is the homeroom teacher of Class 1-B. He is very supportive of his class and beloved by his students, particularly Neito Monoma. Vlad does not want his students to fall behind those in Class 1-A, and for this reason he is always encouraging and supporting them to improve, praising them exaggeratedly when they show signs of progress but he also does not hesitate to criticize them harshly when they make mistakes.

In Forest Training Camp Arc, Sekijiro tells his students to train, so they could surpass Class 1-A. When they are attacked by the League of Villains he was concerned for the well-being. During the Joint Training Arc, he acts as a commentator during Class 1-B vs. Class 1-A battles, making biased comments in favor of his students, to the point that Class 1-A protested for his partisan agenda.