What is the quickest way to get THC out of your system and have already quit smoking for 6 days now?

Some people drink bleach, but it's not recommended. It cannot be relied upon to cleanse your system, and it could easily kill you (or at least, seriously injure you).

There is no way to truly cleanse your system in a matter of hours. You can take detoxifying drinks like Herbal Clean, but these will only mask the THC, not remove it.