Who killed Mahiru in Danganronpa 2?

Danganronpa 2.5: Nagito Komaeda and the World Vanquisher Mahiru later attended Kazuichi’s funeral due to him being murdered by the World Destroyer.

Did Mahiru kill Sato?

Mahiru Koizumi Mahiru cared for Sato very much and always went to the Reserve Course building to eat lunch with her. Sato was very protective over Mahiru and went as far as to kill Natsumi in fear of her hurting Mahiru. Mahiru cried over Sato’s death when she was killed.