Awaiting Green Card Period

Hi
I am currently in the USA for my 90 days allowed, visiting my best friend. I think over time he fell in love with me and i think he might ask me to marry him before my 90 days are over.
My first question is: Is it really dangerous to marry him while i'm here in the US without any special "marrying" visa?
And my second question is: If i do marry him, what happens when i reach the 90 days? Do i need to return to my country even if i'm his wife? Or can i stay in the US with him while awating for my green card?

"Dangerous"? I suppose that would depend on his occupation? He's not an axe murderer, is he? :D

No, it's not dangerous. If he pops the question and you two decide to get hitched right away, you just need to file some forms and drop a PILE of money with the USCIS.

You'll need to file Form I-130 and Form I-485.

Thx for the answer .
I meant dangerous as in, i don't have a fiancee visa.
What do you mean by dropping a PILE of money? and why money?
And can i stay in us even after the 90days as long as i'm his wife? And if i don't have the green card yet?

It costs a lot of money to apply for a green card. It is not free, and it is not cheap - $355 for the I-130 and $1,010 for the I-485 and the associated biometrics fees.

You need to read the links I posted.