According to Dengeki Magazine vol.13, Iruma Hitoma's light novel "Usotsuki Mi-kun to Kowareta Ma-chan" was announced to get a live action movie adaptation. The light novel was remained in the final candidates of the 13th Dengeki Novel Award but didn't won it because of the controversial story. Its translated edition has been published in Taiwan and Korea.

Cove illustration of the novel volume 2
Mi-Ma Image Album official website

Synopsis:
A sadistic mystery novel. The story takes place in a countryside where a missing and a serial murder case occur at the same time. I, "Mi-kun", meet a childhood girlfriend "Ma-chan" again and starts to live with her. I visit her home and there find two missing kids. Ma-chan's mind was completely disrupted by a kidnap and confinement case, in which I and she were involved eight years ago.

Source: Scan of Dengeki Magazine