Speaking with Rogue Magazine, in which he also posed for a stylish photo spread, the Glee alum admitted that he's "so weird about talking about my personal life."
"Deep down, I’m a sentiment hoarder," explained Criss, who recently starred as Andrew Cunanan in Ryan Murphy's The Assassination of Gianni Versace: American Crime Story. "If something is special to me I don’t want to share it with the rest of the world."
Given his desire for privacy, the 31-year-old actor understandably doesn't have a huge presence on social media.
However, somewhat paradoxically, Criss said, "One of my greatest curses, and this is a much deeper thing, is I wish I posted more."
The actor admitted that he's "not a very big social media person" and that he's "horrible" at remembering to post things -- mainly, because he's too busy enjoying the experiences that he would otherwise be sharing with his followers.
"I am too busy doing said interesting s**t, and I think everything is interesting and funny," Criss said. "If I was to take the time and post all that… I would never be observing said interesting fun s**t and I would always be on my phone."
Taking to Instagram in January, Criss shared a heartwarming photo of himself and his fiancée smiling for the camera. "Mia and I have had seven and a half years of fun, wacky, wonderful, CRAZY adventures together," he wrote. "And I’m happy to announce that we’re kicking those adventures up a notch."
"It was a long time coming. We’d waited a while before we announced it," he told the site. "I had a whole thing written, like, ‘Usually I don’t like talking about my private life…’ which I really don’t – I was really allergic to it for a while. Eventually, I got over myself and realized that it’s just the best way to let people know."
Criss' sit-down interview in Rogue Magazine's spring/summer issue is available now. For more on the actor's super sweet engagement reveal, check out the video below.