My friend let me stay at his house but now he's annoying me. I think I'm going to lash out on him.
Why do you want to lash out on your friend?
He is asking me for money
Your friend has been kind enough to give you a place to stay and putting you up is not free. You need to realize that you take up space and use electricity. You are being selfish by not contributing to the household.
He said I could stay here for free. It's not fair to ask someone for money after offering your place for free in my opinion.
You know, you're right. If he did offer for you to stay for free then he should've honored that promise. You should remind him about it and if he still thinks you should pay then unfortunately you have to pay since it's still his house.