Eko to Toru to Mayonaka no Rakurei Shoujo.

is the second volume of the Eko to Toru light novel series, written by Yanagida Kokuri and Illustrated by MACCO. It was released under the Dengeki Bunko Imprint in August 2013.

Synopsis
The second cynical school mystery woven by a human body model talking with a twisted girl!

My name is [Eko]. I don't have any "people" that I can call my friends, but I just recently got to know a "speaking mannequin". There was a rumor that a [suspicious person] was wandering around the school at midnight, and Eko was suspicious. Eko sneaks into school at midnight to clear her doubts, but finds a burnt human corpse on the roof !? "The human heart is invisible. That's why it's not easy to touch. ”A cruel and unhelpful incident encountered by a twisted girl.

(source: Bookwalker JP - Translated)