It's Bloomsday when we sit down to talk and a group of American James Joyce fans have called to the door.
"They've been calling all morning," he chuckles, before pulling out his diary - a large tome of appointments.
Among the first items on his agenda upon taking up residence in the Mansion House was to rehang the 1916 Proclamation on the wall.
"When I came into this office first I noticed a gap on the wall. I asked them what the gap was and was told the Proclamation was taken down.
"I said: 'Would you mind putting it back up?," the mayor says with a smile.
For his time in office, Christy has decided to focus on two main goals.
His main motivation is to tackle the scourge of homeless that has plagued the city.
"For years as a city councillor, I have always fought homelessness and for the right to a home, for the right to dignity of a person or a family who find themselves in that appalling position in life," he says. "I've seen so many homeless cases over the years that would tear you apart.
"I had a woman one night with double pneumonia. I picked her up in Dame Street where she was sleeping on cardboard.
"At the end, I had to get an ambulance. She said she had run out of the A&E, but I convinced her to go back," he explains.
Christy points out that people are becoming homeless from all walks of life and from all areas of the city, from Blackrock to Ballybough.
"If I can arrange and manage to get 10 extra beds for hostel sleepers and if I can get the removal of young women and children and husbands out of hotels and B&Bs, that will be a step in the direction," he says.
Christy's second goal is cultural - he wants a statue of legendary singer and musician Luke Kelly erected in Dublin.
"[It would be a success] if I can get a statue to the great late Luke Kelly, which must come on board, it must come on board," he said. "I got a motion passed 10-years ago at City Hall that a statue be erected. The motion was passed and agreed unanimously. The problem became money.
"Where it will be erected, we have good ideas. The family I'd imagine would love to have it in the north dockland, where Luke grew up, was born and reared," he says.
"If I made an appeal out there tomorrow, set up a Luke Kelly fund, let's get the money, it would be done. If it comes to that, that's what we'll do.
"But I hope that the State, or the semi-State, acknowledge and come on board and let's get the statue of Luke up, let's stop the messing."
Born in Dublin in 1948, Christy left the capital in 1969 late one night on a bus to Derry following a call for republican volunteers to head north.
He explains how he went to see people who might be able to help bring guns to the north, managing to secure a number of arms.
He returned to Dublin, joined the IRA and became "fully active".
He says "everything was dominated by unionism" and he couldn't bare the injustices that he saw at the time. Christy was willing to go to "any lengths" to fight these injustices and for a 32-county republic.
Christy has been jailed a number of times, at first in 1972 for lowering the tricolour in the Garden of Remembrance on Bloody Sunday.
He was sent to Mountjoy in 1973 after being caught in an IRA training camp in Ranelagh.
He was "a player" in the helicopter escape in October that year, when three IRA prisoners escaped from the prison. "It was brilliant excitement," he says of the experience.
Christy was at an IRA office in Dublin in the early 80s when 14 men and women, with a lot of children, called to say they'd been evicted from Ballymun by the Dublin Corporation. It was after helping to secure them houses that he began to make the move into mainstream politics.
The next fight was against heroin, which was invading Dublin at the time and he helped to found Concerned Parents Against Drugs with Fr Jim Smyth.
"It took over my life. Prime Time, or whatever it was, came in and they did an article on it. It took off, the media loved it," he explains.
Christy first stood for a by-election in 1982, securing 2,000 votes. Though he was never elected to the Dail, he stood in the local elections in 1985 and has served on the council since then.
It was the people of areas like Hardwick Street in the north inner-city who convinced him to stand. "I reluctantly stood and I got elected," he said.
He continued his involvement with campaigns and was again jailed, along with Tony Gregory, for protesting on behalf of Dublin's street traders.
Though he celebrates the party's recent electoral success, Christy left Sinn Fein five years ago.
"I was always sort of a loose cannon, I never really complied with the whips or party policy," he says.
"I couldn't handle that people who didn't know my constituency were trying to tell me what to do," he says.
A former IRA man becoming Dublin's first citizen, what would he say to his 18-year-old self if he could travel back in time?
"I'd say: 'You know I'm going to become mayor one day?' Maybe the 'lord' needs to be deleted because it's a British title," he laughs.