Charlie Sheen Says 'Hooker' Knew He Had HIV, Plus She Signed an NDA

Charlie Sheen says the "hooker" suing him for exposing her to HIV is an extortionist, who rolls the dice with STDs on the regular because she's banged "hundreds, if not thousands," of guys.

Sheen is responding to the lawsuit filed anonymously last summer by a woman who says he had unprotected sex with her BEFORE revealing he's HIV positive. In his docs, obtained by TMZ, Sheen says the Jane Doe is completely making that up.

According to his docs, she's a "professional hooker party girl" who gets paid for sex as a high-end escort. Sheen admits he showered her with money and gifts during their less than 2-month-long relationship. He adds ... his HIV positive status was revealed to her the moment they were introduced.

Sheen says she's not only extorting him, but pressuring him by "stalking" his home and his father Martin Sheen's pad, too.

He says the woman signed an NDA before they banged, which requires her to keep quiet about their liaisons ... and to settle all legal disputes in arbitration.