A man's son starts calling him by a different name; soon he finds everyone calling him by that name, and begins to question his identity. Unsettling and presents no clear answers as to why this is happening or what the root cause is. Several possible theories: is this another entity named Yarry, pulling strings? Trying to replace him? Or is he just paranoid and a bad father? The lack of clarity on the true cause makes it great.
Thoughts on endings:
(Spoiler - click to show)The ending where you reject the name is enigmatic and ambiguous. The threat still exists, but it's so ill-defined that you don't know how to fight it. Is fighting it even possible?
The ending where you accept the name took the wind out of my sails a bit. This might just be me, but I wanted a more dramatic replacement scene, where the main character ends up an unwanted stranger in his own family's home. Or something like that. That's just personal opinion though.