Irina is an exceptionally hard worker, to the point of obsession. According to Alisa, after Irina's husband died, she focused entirely on growing the Reinford Group, losing sight of the family she used to care for. She became so focused on expanding the company that she doesn't have the same moral limits that her father, Gwyn, did as company chairman. In further pursuit of company growth, she was willing to go behind the back of her father and force him to resign. The company is now too big for Irina to oversee everything, something that Gwyn disapproves of. Because of their disagreements over how the company should be run, Irina has a strained and distant relationship with her father.
Irina is extraordinarily flexible in everything she does, and shows an immense ability for multitasking. She never stops for a moment to rest, going from one meeting to the next, much to her daughter, Alisa's frustration.
Despite her obsession with her company, she also shows that she still cares about Alisa and her deceased husband. She keeps an eye on Alisa even after she ran away to the academy, reading reports on Alisa's progress. She encourages Alisa to do more than simply rebel, challenging Alisa to take a stand and actually demonstrate what she believes the correct path for the Reinford Group is. She also keeps sentimental items around, such as photos and a watch, that remind her of her daughter and husband, and their old family.
She earned the unwavering loyalty of Sharon Kreuger, for accepting Sharon as the family maid and giving her a second chance in life, despite Sharon's dark past as an Enforcer of Ourboros. She accepted Sharon due to her extreme competence, and values competence in those she works with.
Rean and his classmates first run into Chairwoman Irina in the train station in Roer, on their way to the Nord Highlands in Chapter 3. She greets them there, much to Alisa's surprise, telling Alisa that she had been reading the reports on Alisa's progress and revealing her position as a member of Thors's Board of Directors, alongside the previously revealed Rufus Albarea.