"A classmate still remaining here is the cause of human extinction." That's what it said in the letter from the past, written in the familiar handwriting of my friend. The next day, I decided to go to school, though I can't remember how many weeks it's been since I last went. 'I decided to go search for the culprit' would be a lie, but 'it didn't matter' would also be a lie. "Hey Arata, I almost thought you'd forgotten how to come to school." Oh, アラタ (Arata) refers to me by the way. It's written as 新 in kanji. The kanji is often misread as シン (Shin) though. "Huh, and what'd you come here for Nouko? Come here often?" The students here are what you would call 'the losers'. At least, from the perspective of time travel, they are all classified as useless. I am also one of them.