"I bet we could tie some of them up and abuse them like farm animals," the message read, to which Finlay allegedly responded: "Or the sluts they are."
On a separate occasion, Waterbury claims Finlay wrote a message saying he and another male dancer should film themselves while they "double team" a religious female dancer and "leave her with no choice".
She also claims he sent a nude photo of herself to other male dancers asking: "You have any pictures of girls you've f**ked? I'll send you some ballerina girls I've made scream."
The Columbia University student and model also said there was a widespread culture of males sharing lewd photos of female dancers — and claims one photo was even swapped with a New York pimp.
Waterbury, who plans to sue for an unknown sum, claims the New York City Ballet knew about the rampant, degrading culture but did nothing — which meant male dancers felt they "could degrade, demean, mistreat and abuse, assault and batter women without consequence."
She told the New York Post she had found the incriminating texts and pictures on Finlay's computer.
"These photos were the most embarrassing and degrading thing I have ever faced in my life. I never consented to or even knew that these photos had been taken let alone shared among the employees and patrons of the New York City Ballet," she told the publication.
"Today and every day I will have to say very loudly and very clearly the notorious phrase: Me too."
Finlay suddenly stood down from his coveted role at the company last week, while two other male dancers were suspended.
The company announced the pair "had violated the norms of conduct that the New York City Ballet expects from its employees".
One of the suspended male dancers was also accused by Waterbury of texting Finlay asking for explicit photos and videos.
Legal documents also refer to one incident involving a male dancer who was sent to rehab due to his notorious "substance abuse and domestic violence" — but he returned just days after.
And in another, a male dancer accused of raping one female dancer and assaulting another kept his post "without any repercussions".
According to the Post, New York City Ballet denied it had "condoned, encouraged, or fostered the kind of activity that Finlay and the others named have participated in, which were off-hours activities that were not known, approved, or facilitated by NYCB".
But while Waterbury hasn't yet reported the alleged incidents to the police, she hasn't ruled out pressing criminal charges, lawyer Jordan Merson confirmed.