In the February issue of Cosmopolitan, Mendes -- who plays Veronica Lodge on the hit CW teen drama -- said the on-and-off-screen friends "bonded" over the subject and even had some advice for the fellas: "Don't have sex at me, have sex with me."
"I've never liked this idea of 'don't give him everything.' Like you've given someone all of yourself by having sex with them. What's valuable to me is giving you my love and my intimacy," the actress said. "I want to tell [guys], 'Don't have sex at me, have sex with me.' I want them to understand that it's so much better when we're connected."
Reinhart, who plays Betty Cooper on "Riverdale," expanded on that thought by stressing the sexual experience depends on the unique connection with each partner.
"The idea that sex is going to be the same with everyone -- that's a misconception," she said. "That's how I felt when I lost my virginity -- I was like, 'So this is sex' and then you have sex with someone else, and you're like 'Holy shit, this is so different.' What you want, what feels good to you, it's all going to change with each partner you have."
"Being a young woman in Hollywood is intimidating. I came forward on my Tumblr to talk about my sexual assault story," Reinhart said. "In my situation, I know how powerless I felt because it was my career on the line. It's hard not to think that your next move dictates your career, AKA the rest of your life."
"We have to start thinking about why these men do this and how do we teach the next generation that no one has the power over someone else," she added.
Mendes added that the core of the issue is simply respect for one another.
"How to just respect other human beings," she said. "If I could go back to before I started 'Riverdale,' I would tell myself to speak up when I felt like something wasn't right. To use my voice and know that it's worth hearing."