Mahiru Koizumi is a character in Danganronpa 2: Goodbye Despair, and her title is the Ultimate Photographer. Mahiru is known to be the “big sister” of the group. Sensible and pretty optimistic, she’s very protective of her friends and loved ones and has a strong sense of justice that isn’t afraid to speak her mind. Though she comes off as confident and bold, she tends to have some self-esteem issues - especially about her photography skills, always comparing herself to her mother who was absent in a good amount of her life because of her work as a famous war photographer. She’d always feel frustrated about her skills both because of her self-doubts, but also because there would be others who compared her style of photos to her mother's, and feels like she had a lackluster title despite her love for her craft. Despite being absent from home a lot, Mahiru must’ve seen her as a good mother figure as she still holds her close to her heart, which can’t be said about her father, who always left her responsible for housework and wasn’t as involved in her life either. It’s probably because of her father that she always tends to be tougher on boys. Unlike Tenko, who despises men entirely, Mahiru doesn’t have a hatred for them. However, she seems to hold higher expectations for them and tends to be more stern and abrasive with them. That being said, she tends to be more sympathetic and friendly with girls (some of her closest friends being Ibuki, Saionji, and Mikan).

While she’s extremely helpful and kind, she isn’t a pushover. If someone is being rude (regardless of gender), she won’t hesitate to scold and put them in her place, and will always help take care of others in need (but depending on the person, may complain about it a little). Despite that, she’s extremely empathetic and can never hold a grudge against others who have wronged her in the past. But when something involving injustice is involved, Mahiru’s sense of justice, sympathy, and more raw emotions are shown (seen when grieving for Ult. Imposter and hoping to find his killer, and when confronting Fuyuhiko about being her friend Sato’s killer after playing the Twilight Syndrome game, vowing that vengeance is wrong no matter the reason). 

As a remnant of despair, Mahiru took many horrifying and gruesome photos during the tragedy that would be used as despairing propaganda and news to spread despair to the world. She’d also take photos of some of her fellow classmates and remnants (seen with Sonia in the first episode of the Future arc), possibly as a way to document their influence on those who try to stop them.

I think both voices work for her!

Voices for Reference (ENG): https://www.youtube.com/watch?v=GruFK1xGOmI

https://www.youtube.com/watch?v=MAU72Ocez54