First of, if you're looking for an anime with a similar story, then skip this recommendation.
You're still here ? Okay let me explain ...
Corpse Party : Tortured Souls makes me think to Asura before the end of the first episode and this, in several ways :
First ; the bloody ambiance. It's hard to say much than that without spoiling. Both are clearly gore with an intense amount of violence.
Second ; Asura is a child too. When you decide to drop the innocence of a child to turn him into an adult -or in Asura's case, a beast-, it's a step that can't be reversed. With such accelerated changes, the character lose everything to keep only one thing in mind. In Corpse Party, childrens are ghosts : what ghosts do ? In this case, they're ghosts because they're tormented about something. I won't say more if you didn't see it.
In Asura's case it's about survival, only one thing in mind too. Survive, whatever it takes.
And this is how they confront their situation.
Third ; Psychology. In Corpse Party you'll see each characters evolve due to how they confront the situation (+supernatural, I agree). In Asura you'll follow main character's emotions with is ups and downs, and how he evolves facing the events.
Finally I recommend to see Asura (75min movie) if you're looking for something similar oriented on violence and psychological points. read more
even thought Hotaru no Haka not an action or horror movie , but these two movies share an idealistic story on how can people survive when crisis fall upon them or how they will react, will they change?
Both anime are very dark and mature, set during the Dark Ages, and deal with the harsh reality of life and death in a feudal society, with Asura set in feudal Japan and Berserk set in a feudal England-like setting.
When is it okay to kill? These series focus on this aspect of life. While Shiki is more mysterious Asura is based solely on that. However the moral is the same. Killing others can have serious consequences. Also the reasons people kill each other are very similar in both shows.