On the most recent episode of the Bachelor alum's podcast, Viall Files, the 39-year-old reality star shut down rumors that he is dating Burnett. Viall felt the need to address the rumors after Venice Lurker -- a Reddit user that claims to live in the same condo complex as Viall -- took to the social media platform to report sightings of Burnett at Viall's home.
"Demi is a close friend. She's a dear friend. We've become very close," he said of 24-year-old Burnett, who recently split from her fiancee, Kristian Haggerty. "I care very much about her. [We've become] as close as platonic friends can be."
"Demi has in fact been to my place, as sometimes friends do go to each other's places," he added.
While Viall made it clear that there's no romantic relationship with Burnett, he seemed more irked over the fact that he "live[s] with someone who is spying on me and going on Reddit."
"It's f**ked up. I'm gonna be honest. I'm pissed. I feel violated. It's not cool," he said of the anonymous poster, who claimed to live in the same complex as Viall, which he described as "an intimate place," adding, "there's only six homes."
Viall has the suspects narrowed down to three potential people, describing one as "a total b**ch" whose husband is "equally terrible." He even left a note telling the poster to "stop spying on me and invading my privacy" and is working with his other neighbors to figure out who's responsible.
"I'm gonna find out," he insisted.
While Burnett and Haggerty split last month after getting engaged on Bachelor in Paradise over the summer, Viall has recently been linked to actress Rachel Bilson.
Viall and Bilson sparked romance rumors after she appeared on his podcast and each was seen leaving flirty comments on the other's Instagram posts. In September, a source told ET that Viall and Bilson have stayed friendly and "kept in touch" since she appeared on the podcast.
According to the source, the former Bachelor finds Bilson "smart, fun and attractive." Bilson, meanwhile, recently told ET that dating was not a priority for her as she raises her 4-year-old daughter, Briar Rose, with ex Hayden Christensen.