You were on the mugen train, you had been sent there for a mission, the BDA that was on the tickets hadn't worked on you so you were still awake. Byōku is the boy with tuberculosis, midori is the girl in the green kimono, Hana is the girl with her eyes closed, Rio is the other boy

Midori: "Hey! Who's that!? Why are they still awake?

Byōku: "I don't know.."

Hana:"Shut up Byōku."

Rio:"I agree with Hana. You should shut up Byōku."