Shannen Doherty's Heathers Costar Praises Her 'Courage' with Cheeky Nods to Cult Classic: 'You Always Had the Balls'

Lisanne Falk is sharing a tribute to her late Heathers costar Shannen Doherty, while referencing their cult classic.

On Monday, July 15, Falk posted a film still of herself and Doherty in the 1989 dark teen comedy, in which they played Heather McNamara and Heather Duke, respectively, alongside Winona Ryder as Veronica Sawyer and the late Kim Walker as queen bee Heather Chandler.

Falk, 59, began by admitting she "felt quite conflicted about whether I should post anything about Shannen’s passing" after the news of Doherty's death on Saturday, July 13, as they "weren't friends" and hadn't spoken since Heathers was released and "defined us both in a public fashion."

But after recently listening to Doherty's Let's Be Clear podcast "by chance," Falk went on to say that she "was genuinely moved by" her former costar's "desire to ‘set the record straight’ as she owned up to some of the uncomfortable hunks of truth in her past."

"We’ve all got them. Yet Shannen’s courage in addressing them publicly as her health deteriorated, well, there is really only one response - How … very!" Falk continued, referencing one of the famous quotes in the movie.

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Falk went on to say that she was "truly saddened to hear the news" about Doherty, who died on Saturday at age 53 after years of living with cancer.

"And if her portrayal of Heather Duke were to serve as her epitaph, I, for one, as the last remaining Heather would think it more than sufficient," she wrote. "Certainly no one else could have landed the line: ‘Veronica, why are you pulling my dick?’ like Shannen did."

Falk also referenced the death of Walker at age 32 back in 2001, writing, "Tragically, Heather Chandler never had the chance to reflect, and now Heather Duke was interrupted just as she was clearing her throat."

"If it is Heather McNamara’s fate to have the last word for the Heathers, then let it be this: It’s been an honor to occupy our own little patch of the zeitgeist, together as one, out here on the fringe, where all the cool kids hang, a cult classic," she continued.

"Thank you, Heather. And Heather. ❤️💚💛," Falk added, using heart emojis in the signature colors of her, Walker and Doherty's croquet-loving characters. "May flights of angels sing thee to thy rest, Shannen. You always had the balls, didn’t you? For better or worse, no more pulling your dick."

Among the comments was one from the director of Heathers the Musical, Andy Fickman, who praised Falk, "So Very … Beautifully said. Love you! Xo."

Doherty's longtime publicist Leslie Sloane confirmed the Beverly Hills, 90210 star's death in an exclusive statement to PEOPLE on Sunday, July 14.

"It is with a heavy heart that I confirm the passing of actress Shannen Doherty," she said. "On Saturday, July 13, she lost her battle with cancer after many years of fighting the disease."

"The devoted daughter, sister, aunt and friend was surrounded by her loved ones as well as her dog, Bowie," Sloane added. "The family asks for their privacy at this time so they can grieve in peace."