Until Dawn doesn't pull any punches when it comes to representing gore. It can get down right grizzly at some points, never shying away too much from the nasty of what is happening.
It appears that it in fact, it might be a little too hard edge for Japan. As Kotaku report, certain scenes are getting obfuscated in the country, cutting to black during specific scenes. Japan actually have a history of censoring portions of games, so this isn't the first time it has happened.
To see what has changed, take a look a this video from Censored Gaming. Big spoilers await you here though, so do be careful.