Heavy Object (ヘヴィーオブジェクト, Hevī Obujekuto) is a Japanese light novel series, written by Kazuma Kamachi who also wrote A Certain Magical Index starring Kamijou Touma and illustrated by Ryō Nagi. ASCII Media Works published the series in twenty volumes from 2009 to 2021 under their Dengeki Bunko label. It has received three manga adaptations. A 24-episode anime television series adaptation produced by J.C.Staff (with 3DCG provided by Sanzigen) aired from October 2015 to March 2016. Source: Wikipedia (en)