I'm the only one

The howl that came from his jaws echoed into the night air, filtering through the bamboo before the thick stalks swallowed the sound whole. It was replaced with silence, a silence so prominent that he felt as though he could hear his heart racing in his chest. Then, the pain began. His heart gave a stutter, then the silence became louder when he could no longer hear his heart beat at all. He felt dizzy and pain bloomed in his chest, and he knew his heart had to have stopped. His panic grew and he let out a gasp for breath, a louder whine coming from him this time. Oh god, was he going to die? He didn’t want to die, not like this, not without saying goodbye and not without working things out with his father. Then, a few short moments later, his head stuttered back to life and he released a breath of relief, though the pain was still fresh in his mind. What had just happened, and why?