Enji Todoroki/Relationships

Rei Todoroki
Rei is Enji's wife, however the relationship between them is far from a happy one. Enji only married her to conceive a child capable of surpassing Toshinori Yagi, showing that there was no love between them from the very beginning. When Enji began training Shoto to become a Hero, his wife tried to stop him, but Enji refused to listen and told her to stay out of his way. Enji would constantly abuse her which led her to a psychotic break. Enji then admitted her to hospital, but not for her own sake but rather so that she would not interfere with Shoto, showing no form of care or compassion.

It was mentioned that he has been visiting his wife at the hospital often, though he hasn't seen her face to face. He left her a flower that she once told him she liked. It was used to show that while even as the number one hero that he has not forgotten about the past. This implies that he does have some care for her, in spite of his cruel actions towards her.

Shoto Todoroki
Enji is Shoto's father. Their relationship is poor: Shoto grew up experiencing his father's abuse not only towards him but also his mother. As explained during the Sports Festival, Enji regards Shoto merely as a tool to surpass All Might, seemingly because Shoto possesses a perfect mix of both his parents' quirks, something his other children do not. As a result, Enji put Shoto through ruthless "training" which caused Shoto a severe degree of physical and emotional pain. Shoto, harboring a bitter hatred towards his father on account of this as well as the abuse towards his mother, refuses to use his fire powers in battle until Izuku Midoriya reminded him of his mother's encouragement.

After Shoto used his fire power in battle, Enji was visibly excited, although Shoto still made clear to him that they were not on good terms. Nevertheless, Shoto accepted his father's field training offer, showing that he realizes his father's success as a Hero.

Enji later expressed pride in his son after he succeeded in his Hero license exam - he called him his son not his tool as he previously done. Enji tried to pat his son on the head, though Shoto gave him the cold shoulder. Undeterred by this rejection, Enji simply told his son he would try to be a better hero and man that Shoto could be proud of. Shoto simply shrugged him off, but smiled to himself in response.

Enji and Shoto met again after his battle with High-End, Shoto brought up Enji's scar and spoke rather tensely to him. Once Natsuo confronted Enji and left, Shoto spoke up and called him a great hero after his success. Enji was surprised and listened as Shoto voiced while he hasn't forgiven him yet, he sees the changes he is making while looking forward to seeing what man he would become.

A sign of Enji trying to improve his relationship with Shoto is when he tries to contact him on his phone to teach him a new move while reflecting on how he treated him in the past and how he wants to support his son on the path he has chosen.

Other children
Due to them not inheriting a powerful Quirk to surpass All Might, Enji deemed them failures and did not put much thought into their upbringing, even forbidding their brother Shoto from playing with them when he saw him watching them. While it is unknown if he was abusive to them, his daughter Fuyumi was nervous about Shoto meeting their mother but doesn't appear to resent him. His second son Natsuo mentions that he hardly remembers him, which means that Enji did not do much in raising his oldest children. It was also suggested that Enji tried to train his oldest son Toya since he had a fire quirk that was said to be more powerful than his, though he labeled Toya to having his mother's weak constitution preventing him from improving it. He also called his unknown accident as unfortunate but he didn't show remorse in causing it.

After deciding to change and promising Shoto to become a better man, it has yet to be seen if he will extend this side to them as well. However, Fuyumi and Natsuo were surprised to hear their father visited their mother at the ward and seemed perplexed by her words of him facing an internal conflict. During his fight with the High-End, Enji thought about his oldest children and remembered why he started a family.

After he returned home, he found his children eating dinner. Fuyumi put an effort to congratulate him on his recent success while he took it in stride. Natsuo and Shoto tensely glared at him and only spoke up about his new scar. When Natsuo moved to leave, Enji stopped him and told his son to speak up. With this, the latter angrily confronted him on everything he's done, even saying he's incapable of change and blames him for the distance between him and Shoto, as well as what happened to Toya. Enji simply remained silent at the rant before calmly stating he will face his past to atone. Natsuo was surprised by this statement and left. Enji spoke with Fuyumi and stated he chose the wrong words with Natsuo.

All Might
Ten years before the start of the series, Toshinori once had a talk with Endeavor and since then, they have not spoken to each other. It appears that Endeavor has an intense rivalry with Toshinori (one sided on Endeavor's side as Toshinori tries to be friendly with him). This rivalry with Toshinori is so great that Endeavor decided to have a child that would be able to surpass All Might. Endeavor despises Toshinori's "easy breezy little attitude", finding it to be annoying. Despite his antagonism to All Might, Endeavor does have a begrudging sense of respect for his skills and strength.

However, upon learning and seeing his true form, Endeavor was furious that his rival's true form was so meek and small. His disdain of All Might only intensified after the latter retired as a Pro Hero and Endeavor would be given the No. 1 spot, which he always wanted but furiously refuses it, due to the fact he did not earn it nor does he feel he deserves it.

Despite this he is not incapable of showing All Might respect, as he thanked All Might for bringing his son back to him. He sincerely asked him later how he was such a capable Symbol of Peace.

Hawks
Enji did not like the young heroes' attitude and was especially annoyed when the latter made comments on him. However, he kept his composure and agreed with some of them. Later, he confronted Hawks on his snarky attitude and the latter explains that he tried to help Endeavor on the podium as he sees that Endeavor is fit to be a new leader to support everyone after All Might's retirement. Enji almost left dissatisfied, though Hawks requested a team-up as he needed his help in investigating concerning sightings of Nomus.

Hawks later aided him in defeating High-End and congratulated Endeavor on his victory.

Dabi
Enji met him after defeating High-End and was confused by the latter's familiarity with him. Enji soon recognized him as Snatch's killer and was disgusted by his callous disregard for the hero. The villain would try to attack but would retreat after more heroes appeared though told Endeavor they would meet again while calling him by his true name.