BAKEMONOGATARI (Manga) Volume 21 - NISIOISIN, Oh! Great

One day, high-school student Koyomi Araragi catches a girl named Hitagi Senjougahara when she trips. But - much to his surprise - she doesn''t weigh anything. At all. She says an encounter with a so-called ''crab'' took away all her weight... Monsters have been here since the beginning. Always. Everywhere.