※估算 根据卷数、再版次数、连载杂志等推算的参考值(非实测)
作品概要
Six years have passed since the grade schooler Manato disappeared during a school trip. Now his little sister returns to the city where everything started and meets an old friend of her brother, Atsuma, who is happy about her coming back. But the happiness doesn't last for long since Manato's former classmates are suddently getting attacked by some unknown enemy who wants to see them dead.
来源: AniList
How to compare editions, collected volumes and ISBNs / Sources, updates and corrections