They are teamed up together as Team I during the Battle Trial Arc.
Afterwards, they are often seen talking with each other.
After the villains retreat during the U.S.J. Arc, Toru commends Mashirao's strength, while he asks where she was transported to. After she tells him she was in the landslide zone and mentions Todoroki's strength, he comments that he's glad she was alright. During the final part of the Sport Festival, when Mashirao wants to withdraw from the tournament event, she tries to persuade him to reconsider.
They get along well though Mashirao didn't team up with him since Izuku was a target in U.A. Sports Festival Arc. Despite that Mashirao tried to warn him about Hitoshi Shinso, Izuku also stood up for him after Shinso insulted him. Mashirao worried for him but was relieved he emerged from the fight victorious.
Ojiro sits in front of Denki in class and the two are often pictured talking to each other in the background, implying a friendship. Denki seems to have a fixation on Mashirao's tail and often plays with it and pets the hair on the end of it.
The two were partnered up during the final exams against Power Loader. They were shown to work and get along well. During the exam they showed trust in each other as they used the combined power of their quirks to throw Ojiro through the gate resulting in the two passing.
Mashirao resigns from the tournament event in the Sports Festival due to being manipulated by Hitoshi, wanting to save his own pride and dignity by doing so. As a result of Hitoshi's action, Mashirao has come to dislike him because he prevented him from doing his best. When Hitoshi approaches Izuku, Mashirao warns Izuku not to respond to his provocations.