Answer
Atsumu Matsuyuki, voiced by Yoshimasa Hosoya, is a crucial character in the anime series "Anohana: The Flower We Saw That Day." He is a former member of the group of friends known as the "Super Peace Busters" and plays a pivotal role in the central mystery and emotional journey of the story. Atsumu's character development and interaction with the other characters provide depth and resonance to the overall narrative.