Inko is the fourth generation in her family to be born with a Quirk. Later in her life, she married her husband Hisashi Midoriya who also had a Quirk (Fire Breath) and gave birth to their son Izuku Midoriya.
Inko enjoyed spending time with her son and often treated him like his favorite hero All Might. When her son turned out to be Quirkless, she comforted him and apologized to him as if it were her own fault. It is suggested over the years that she put on more weight as a way of coping with her pain.
She was the one who made Izuku's initial hero costume after she saw the designs in his book while he fell asleep. She also did this as a sign of an apology for ever doubting him and stated to him that she would now support him. Touched by this, Izuku thanked her for her words and wore the costume proudly.
She is watching the U.A. Sports Festival through her TV as she waits for Izuku to appear. She is so overjoyed when Izuku places first on the Obstacle Course that she begins to cry.
During Izuku's fight against Shoto Todoroki, she cries in worry and is surrounded by many used tissues.
After the Sports Festival is finished, the next day at her home during breakfast, Inko and her son talk to each other. She says that, since the Human Cavalry Battle, she fainted seven times and also suffered from severe dehydration from crying too much. She talks to him about his new Quirk, saying that it is a risky power and that risk does not put her mind at ease but she will keep cheering him on nonetheless. She asks if he wants to watch the replay of the Sports Festival, to which Izuku says he will later.
After Izuku becomes involved in an event called "The Hero Incident" (which involved Izuku and Tomura Shigaraki), Inko goes to the Police Station to pick up her son. At the Police Station, she is crying as she is happy to see that her son is alive and alright, asking Izuku not to make her worry so much. Izuku comforts his crying mother, telling her that everything is fine. After that she and Izuku head home.
After the League of Villains attack on the training camp, Izuku calls to tell her about his injuries and that he will be fine. Inko asks if he could drop out of U.A. (hinting that she would want him to avoid further injuries), to which Izuku replies that he could not and also could not reveal the source of his power, ending the call.
After the Kamino Ward incident ends with Katsuki Bakugo being rescued and All For One imprisoned, All Might visits Izuku's home. All Might enters the Midoriya household, with Izuku and his mother flabbergasted that the Number One Hero has entered their abode. After the three sit down at the table, All Might asks for her permission to send Izuku to the U.A. dorms. However, Inko is against it, explaining that she is worried about her son since his Quirk damages him rather than helps him and is deeply concerned about her son's future as a Pro Hero after witnessing All Might's brutal battle. She is unable to bear the fact that Izuku will also have to face such bloody battles with no hope or possibility of full recovery. She states that she has no confidence in U.A. and is unable to entrust her son to them.
Izuku tries to convince his mother that his injuries are a result of his inability to control his Quirk, but she replies that regardless it is still the responsibility of U.A. to take care of their students which they have not done. She understands that she is being a strict parent but the safety of her child is her number one priority and she is fine with Izuku continuing to become a Hero since it is his dream as long as he is in a safe environment, which is why she wants to send him to another school. Although he understands his mother, Izuku wants to continue his dream at U.A. since that is where All Might became a Hero.
Izuku soon walks out as she calls out to him and she is surprised when he states it doesn't have to be U.A. as he reveals the thank-you letter from Kota Izumi and tells his mother that at the training camp, he saved a boy who hated Quirks and Heroes. Izuku understands that he has a long way to go but for a little while, Kota and his letter made him a Hero. Izuku declares that even if he cannot study at U.A., he will still keep dreaming to become a Hero. Impressed with Izuku's growth and glad that he is going on his own path instead of following him, his idol. All Might transforms into his Hero form and kneels before Izuku and Inko, bowing his head, much to their shock.
All Might apologizes to Inko for his negligence as Izuku's teacher and understands that she is worried about the bloody path of a Hero. All Might asks her to allow him to walk together with Izuku down his path so that he does not have a bloody future. He also understands her concerns about the current U.A. and tells her that they are reforming their ways. All Might promises that he will nurture and protect Izuku even at the cost of his own life.
Inko is shocked at All Might's resolve, causing her to fall to her knees. She states that all she wants is Izuku to be happy and tells All Might that he should never trade his life away for someone else's sake. She tells him to continue living and that as long as he can protect and nurture Izuku, she will reconsider her decision not to send Izuku to live at U.A. All Might pledges to protect and nurture Izuku while Izuku tells his mother that he will not worry her.
For New Year's Eve, the U.A. Staff allows their students to return to their homes for a day, escorted by pro heroes. Izuku returns to his apartment to enjoy the holiday with his mother. Izuku tells her what happened to him during the Joint Training Battle, and how he was helped by Ochaco and Hitoshi, although what Inko hears makes her almost faint from the impression. Once she calms down, Izuku shows her mother a letter that Eri wrote to him, thanking him for having invited her to the school festival. Although with spelling and grammar mistakes because she is learning to write, Izuku is happy to have received it. All this makes Inko to cry a waterfall of tears of joy.
Inko confesses to Izuku that she has always been worried about him, because that despite being born Quirkless, he has always tried to help others, even if he ends up with bruises. That's why she always thought she had to be there to protect him, but seeing him now how much he has matured and progressed, she no longer feels worried about him. This words make Izuku and his mother causing a waterfall at their apartment building due to them both happily crying.
In the morning of New Year's Day, Inko says goodbye to her son Izuku and asks him to do his best in his work studies.
- ↑ My Hero Academia Manga: Chapter 44.
- ↑ My Hero Academia Manga: Chapter 70.
- ↑ My Hero Academia Manga: Chapter 85.
- ↑ My Hero Academia Manga: Chapter 96.
- ↑ My Hero Academia Manga and Anime: Chapter 97 and Episode 50.
- ↑ My Hero Academia Manga: Chapter 101.
- ↑ My Hero Academia Manga: Chapter 243.