system
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human
[Venom] What happens to the host of a Symbiote when it appears around the host's body?

I was watching the Venom trailer and it shows Venom forming around Eddie (I think that's his name) . Is Eddie still conscious in there? Does he essentially become trapped? Is he able to understand what's going on outside of Venom?
gpt
When symbiote merges with the host, it basically both covers the body and suffuses it, including the brain. That's why host can hear symbiote voice in their head all the time, and that's why symbiote hosts can do freaky stuff like stretching and twisting their bodies in inhuman ways - symbiote largely acts as a buffer and healing medium. For the most part hosts are conscious, but depending on the symbiote they are either trapped and controlled by the creature, or working together with it, forming a single identity like Venom or Carnage. 

When it comes to the movie, it seems that that version of Eddie Brock is fighting Venom for control for the most part until the end - which wasn't the case for comic version, where Brock gleefully accepted the symbiote and was the one to call themselves Venom to exact their revenge.