See Robert Pattinson's Reaction to His 'Batman' Nicknames (Exclusive)

The leading man also joked about how his boyish looks made another role difficult!

Robert Pattinson hasn't exactly warmed up to all playful nicknames that fans are giving him since news of his hotly anticipated upcoming role as Batman was revealed.

ET's Ash Crossan spoke with the 33-year-old actor at the Toronto International Film Festival on Saturday, where she asked whether he prefers R-Batz or Battinson, to which he offered a big grin and replied: "I don't know ... I'm trying to avoid... avoiding nicknames."

Pattinson was on hand to promote his starring role in Robert Eggers' new harrowing film The Lighthouse, admitting that one of the challenges of the production was maintaining his dark, imposing mustache, which isn't naturally as dark as his character's. 

"The only thing about the 'stache is I had to keep dying it all the time because my mustache is very blonde, so it kinda looks like…like I'm a 12-year-old with a hormone problem," he explained with a laugh.

The leading man also chatted about the extreme conditions of the film, which included lots and lots of water, and filming on location in Nova Scotia. However, he shared that he appreciated the extreme elements he faced while filming because they helped him immerse himself in the story.

"The conditions are nice though," he told reporters. "It's nice when something feels real."

In the film, he plays Ephraim Winslow, a lighthouse keeper stuck on a remote island with one other man, Thomas Wake (Willem Defoe), as they brave massive storms, isolation and the slow decline of their own sanity.

ET also spoke with Defoe after his and Pattinson's arrival was met with an outpouring of screams from onlookers.

"Is that all for me?" he joked, subtly referring to his heartthrob co-star's feverish fandom. However, while discussing how his prominent beard in the film measured up to Pattinson's mustache, he proclaimed of his facial hair, "I think I won!"

ET confirmed in May that Pattinson will be starring in Matt Reeves' The Batman after multiple outlets reported the casting news. His Twilight co-star, Kristen Stewart, couldn't help but praise the casting while speaking with Variety at TIFF.

"He's the only guy that could play that part; I am so happy for him. It's crazy," she shared. "I'm very, very happy about that. I heard that and was like, 'Oh man! Yeah, that's awesome!"

The Lighthouse hits theaters on Oct. 18.

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