A 24th female masseuse has just filed a lawsuit against Deshaun Watson ... alleging the NFL star was sexually inappropriate with her during a massage session -- and the new allegations are graphic.
In the suit, filed in Harris County, Texas on Monday, Katy Williams claims Watson got in contact with her back in 2020 to set up a professional rubdown.
On Aug. 5, 2020, the woman says she massaged Watson without issue -- and the quarterback gave her $100 for her services.
A few days later, however, Williams says during a second massage session with the QB, which she says took place at her apartment, he became very inappropriate.
Williams claims in the suit that Watson asked her to rub his inner thighs, and then demanded she go higher and higher, which caused her to touch his scrotum.
In the docs, Williams says Watson eventually got an erection, and then stood up and masturbated. She said he ultimately ejaculated, and some of his semen got on her chest and face.
She says in the suit she ran away from Watson into a bathroom to clean herself off -- and claimed when she returned, the 24-year-old "offered no apology or explanation for his conduct."
Williams said in the suit he then paid her $150, and left. She claimed in the docs the incident left her "humiliated and traumatized."
She added that she quit massage therapy a short time later. She's asking for damages in the suit.
Williams' attorney, Tony Buzbee -- who's representing Williams and 23 other women in the civil cases against Watson -- said in a statement of the new lawsuit on Monday, "Our entire team is incredibly proud to represent these women, and we look forward to the day when we can lay out their cases in detail in front of a jury."
Watson, as we've reported, has repeatedly denied any wrongdoing ... saying at his Browns introductory press conference earlier this year, "I never assaulted any woman, I never disrespected any woman."