Yesterday, acclaimed American electronic musician Porter Robinson released an anime. Shelter is the short and tender story of a girl living alone in virtual reality, rendered by Japanese animation studio A-1 Pictures. It has received overwhelming praise over the last 24 hours. And, after its swift removal from Reddit's 420,000-strong anime subreddit, Shelter has also become the latest peg in the debate over what actually defines "anime" -- a debate that has apparently resulted in death threats to /r/anime moderators.