'A proportion of us have penises and another proportion have seen them... so I don't know why it's so unusual to show that in a movie'
Somewhere between talking about male genitalia and his own sex life ("healthy", in case you can't wait to find out), Michael Fassbender's conversation with Day & Night swings round to the topic of nicknames.
Inspired by 'Cumberbitches', the elegant collective name for fans of British actor Benedict Cumberbatch, we start spitballing potential titles for Fassbender's own fast-growing posse of devotees.
'Fassbenders' is an obvious pick, though one might have to concede that that's probably only suited to his gay fans. Similarly, 'Mickey Addicts' might be just a tad too rude.
"'The Fasscinators' is one," he says in a surprisingly neutral, mid-Atlantic accent that, by the end of our chat, has defaulted back to his Co Kerry roots.
"I remember when I was working on Eden Lake, the kids used to call me 'Fassy B'. I've been called worse, let's put it that way. Primary school was open season. I'm sure you can imagine the various spins that were put on my name. See what happens then? You become an actor."
And what an actor Fassbender has become. The 34-year-old is currently enjoying the kind of breakout success for which most actors would sell their firstborn. Last year, we saw him play the young Magneto in the blockbuster X-Men: First Class, followed by an intense and swarthy Mr Rochester in Jane Eyre.
In the coming weeks, moviegoers will also see Fassbender in leading roles in Steven Soderbergh's Haywire and David Cronenberg's A Dangerous Method, in which he plays seminal psychiatrist Carl Jung.
Right now, however, Fassbender's focus is on Shame, which re-unites the actor with the artist-turned-director Steve McQueen following Hunger, their acclaimed account of the 1981 IRA hunger strikes, in which an emaciated Fassbender played Bobby Sands.
In Shame, Fassbender plays Brandon, a young, successful New Yorker, who, it quickly becomes clear, is also a sex addict. His carefully controlled private life -- incorporating porn, encounters with prostitutes, and more besides -- starts to unravel, however, when his troubled younger sister Sissy (Carey Mulligan) arrives on his doorstep for an indefinite stay.
Fassbender's performance is shattering, and stark in every sense of the word. It's garnering him major critical kudos, too. He has already been awarded the Best Actor prize at the Venice Film Festival, and has picked up a Golden Globe nomination for next weekend's ceremony. There's every chance that he could end up on the Oscar shortlist when nominations are announced on January 24.
McQueen first suggested the idea for the movie to him after Hunger in 2008. "It seemed like such an obvious thing to do because there was so much in the media at the time about the idea of modern-day sexual relationships, and our relationship to sex and one another, and in that environment, the concept of sexual addiction," he explains as he settles on to a sofa in London's Soho Hotel, trusty packet of Marlboros positioned in front of him on the table.
"When you start looking into it, the vast number of millions of people in America alone who claim to be sexually addicted is pretty staggering, but then, at the same time, it's not officially recognised as a disorder or addiction. So there's room there for argument and conversation and investigation. Certainly nobody was really dealing with it in the film world."
In the course of his research for the part, Fassbender met several sex addicts in the US. "It's pretty sobering," he says. "Initially you might laugh at the idea of sexual addiction, but it becomes very serious pretty quickly when you see the devastation that it leaves in its wake.
"But there seems to be some kind of stigma about it. It seems more acceptable to deal with alcohol or drug addiction.
"What's interesting is that drugs or alcohol are outside influences that you bring in, whereas sex is within us. It's something that's innately there and is part of our make-up and instinct, and so when that becomes imbalanced and reaches an unhealthy situation, what do you do with it? Do you totally abstain, or do you try to negotiate life?"
Rather cheekily, I remark that working on a project like this and immersing oneself in such a world would probably flush out any issues or hang-ups an actor might have regarding their own sexuality.
Fassbender smiles. "I could relate to certain elements of Brandon," he says. "A lot of guy friends I've spoken to since then have said the same thing. But what has really struck me is how grateful I am to have a healthy relationship with sex and my own sexual life. I like intimacy, whereas Brandon flinches at the notion. There's no gratification in his sexual acts. It's just a compulsion, with no nourishment or pleasure."
The part also requires Fassbender to be fully naked on screen a great deal, including more than one full-frontal scene. Is it safe to assume he won't be taking his mammy to see the movie anytime soon?
"She was meant to be in Venice with us, but thank God her back played up at the last minute," Fassbender laughs. "I don't know if that's psychosomatic. She'll watch it, but I won't be there."
Was he at all embarrassed to let it all, ahem, hang out there on the big screen? "The thing is, we were making a film about a sexual addict, so obviously I'm going to have to get naked," he replies.
"I felt self-conscious, and it's awkward, but I had to get over that pretty quickly because I knew that within each scene there was an opportunity to reveal another element of the condition of the character to the audience.
"So by concentrating on that you get over the fact that you're stark-bollock naked. It's not that big a deal, anyway. A proportion of us in the human race have penises and another proportion of them have seen them, whether they be mothers, girlfriends or partners or whatever, so I don't know why it's so unusual to show that in a movie."
You'll agree it's all very risqué talk for a boy from Killarney. Born in Heidelberg to a German father and Irish mother (a distant relative of Michael Collins), Fassbender was two when his parents relocated to the Kerry town to run a restaurant.
Fassbender moved to London at age 19 to study acting, and landed a gig on Steven Spielberg and Tom Hanks's Second World War series Band of Brothers right after graduating from the London Drama Centre. However, for most of his 20s, Fassbender was a jobbing (ie, struggling) actor, requiring him to hold down a steady nixer as a barman in various London nightclubs.
After appearances in TV productions such as William and Mary, and The Devil's Whore -- not to mention a famous Guinness ad where Fassbender's character swims to New York to apologise to his brother -- Fassbender's luck started to change with movie roles as a Spartan in 300, in urban horror Eden Lake, and Hunger, which won him a string of critics' prizes.
A well-received turn in the startling Fish Tank bolstered his image as a fast-rising indie star, while his performance in Quentin Tarantino's rollicking Inglourious Basterds proved he was equally adept at handling the mainstream material.
This past year has been the game-changer, however, but Fassbender seems well equipped to deal with impending superstardom, as well as intensified focus on his private life (he's rumoured to be dating his 23-year-old X-Men co-star Zoe Kravitz, daughter of singer Lenny).
"Let's see what happens," he says. "To keep doing a certain quality of work is my main concern, and keeping things simple is the best way to go about it as far as I'm concerned.
"I'm in a 1pc position now. To be a jobbing actor was already an amazing prospect for me when I was out of work and working behind the bar. So I really can't complain. I'm very lucky."
He adds: "Being 34 and a bit older, I guess I realise how quickly it can come and go. I'm aware of how fragile the position is and how much responsibility I have. It means a lot of the distractions that come with the business don't really interest me that much, and they might have done when I was 24.
"For me it's pretty simple: it's all about the work."
Shame is in cinemas on January 13, Haywire is released on January 20 and A Dangerous Method
is out on February 10
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