Sisu is the mother of Ezra.
Sisu was born in Vasa (Finland) in a farming family. Due to increasing vermin infestations, Sisu had to move away from home earlier than many of her peers, which affected her psychological well-being. After living a few years in St Petersburg (Russia) working as a carpenter, Sisu eventually moved to Stockholm (Sweden), where she met Urhea, with whom she parented Ezra. After her husband enrolled to fight in the Global War, Sisu took care of Ezra herself. She worked as a construction worker during the day and worked extra in a local grocery store at night. And after realising her husband's death, she became increasingly over-protective of Ezra. She went so far as to plant a chip into Ezra's brain to keep track of him. Little is known about Sisus life after Ezra left home, as well as her death. Her death was never confirmed. She is believed to have died of radiation or possibly by explosions during the June Revolt since she might have been working at the parliament at the time due to restoration work.