Mahoro Shimano/Relationships

Katsuma Shimano
Mahoro cares and loves her brother Katsuma very much. Due to the premature death of her mother and because her father is usually absent, Mahoro is responsible for taking care of her little brother and making sure that nothing bad happens to him. Both siblings help each other when one has problems.

The only thing they didn’t agree on is their opinions about heroes since Katsuma admires them but Mahoro did not have a good opinion of them and tried, by all means, to show her brother that they are not as great as he thinks, and wanted to discourage him from ever becoming one. That's why she made her brother participate in her antics towards heroes. Her attitude was not because Mahoro just hated heroes, but she wanted to stop Katsuma from every thinking of becoming one because she knows hero work is dangerous, and she doesn't want anything bad to happen to him.

This attitude changed during Nine and his gang's attack on Nabu Island, where both siblings used their Quirks to help each other and help Class 1-A students. Mahoro even stood between his brother and Nine to protect him.

Mr. Shimano
Like his brother, despite the fact that Mr. Shimano is usually absent due to his job, Mahoro loves her father very much and always looks forward to his return home. Sometimes she tells her little brother that her father is greater and better than any hero. When their father must leave the island for work, she makes sure he doesn't worry about them, assuring him that she will be responsible and she will take good care of Katsuma.

The first thing she did after Mr. Shimano returned to Nabu after being attacked was run to meet him at the port and hug him.

Izuku Midoriya
Due to his antipathy towards heroes, Mahoro did not have a good opinion of Izuku at first, making him the victim of several of her antics to show her brother how useless heroes really are. Izuku's kind nature did little to change that idea, and Mahoro even scolded Izuku for being late to "help" them, to which Izuku apologized.

Everything changed with the attack of Nine and his gang on Nabu Island, where Izuku fought with all his might to protect her and Katsuma, even at the cost of his own life. This made her change her view of heroes. When Izuku gave a speech she was filled with hope and was amazed how he rallied the other Class 1-A students behind him. After defeating the villains, their relationship improved greatly, and since then Mahoro respects Izuku.

Katsuki Bakugo
If Mahoro's first impression of Izuku was bad, her first impression of Katsuki was even worse. Mahoro also played a prank on Katsuki, but unlike Izuku, he reacted violently, to the point where Izuku had to hold him down out of fear that he would punish both siblings with excessive severity. This caused that at first Mahoro considered Katsuki a brute and a violent person, and she didn't take seriously his claim that he would be the next number 1 hero.

With Nine's attack, her opinion about Katsuki improved, since like Izuku he did everything possible to protect her and her brother, saving her on several occasions. When Katsuki once again told her that she would be greater than any other hero she was awestruck. This admiration made Mahoro even develop a small crush on him, reaching the point of blushing when she saw Katsuki being kissed by Recovery Girl in order to heal his wounds.