The Demon's Heart : Hell On Earth

Matt, a cold-acting and a pessimistic boy who is scared of helping anyone in need as he thought he might make it worse or end up being hurt, goes to a construction site with his close friends Maria, Bayrauk, Scylla, and Cassie. Matt finds a black heart inside of a semi-transparent purple prism that seemed to beat slower than that of a human's, unlike his friends who found weird hexagonal stones each with an animal's face on it: an eagle(found by Maria), a bear(found by Bayrauk), a cobra (found by Scylla), and a bat(found by Cassie) Matt kept it a secret

Later that night, Matt decides to walk around a garbage dump to check if there were interesting things to collect since he couldn't sleep because of the slow heartbeats of the heart he found in the construction site. He loses track of time and goes deeper into the garbage dump where he finds what looked like a beggar searching for something to eat near the garbage incinerator and, for the first time, he decides to help and gave the beggar some money which, for unknown reasons, drives the beggar mad and pushes Matt into the garbage incinerator.