Yamato was 11 when he first met Benjiro. They would play around Mr. Kimura's store as he worked on his wood carvings. Before Mr. Kimura left on a business trip, he gave Benjiro a tengu mask and Yamato an oni mask. That day, Yamato heads home to show off the mask to his mother Ichika.
Yamato: Mama look, Mr. Kimura made me this. Now I can talk to you without worrying about your sickness.
Ichika: That's great to hear Keito, but you still need to be careful...
She starts coughing and Yamato runs to get her some medicine.
Yamato: She's starting to forget my name again.
As he heads to get the medicine, he sees his father Daichi.
Daichi: I keep telling you, we're wasting our trying to take care of her. That mask, you got it from that store didn't you?
Yamato: Yes...
Daichi: I told you to stop going over there.
He rips the mask off of Yamato's face.