Said Ms Tobin: "He was definitely the best-dressed man at the races - very handsome."
The pair, then aged 47 and 24, hit it off. On their return to Perth, Mr Papaspiropoulos wooed Ms Tobin with poetry, music and old movies.
Both were born on February 24 and say they share similar star-sign traits.
"We're both Pisceans," Mr Papaspiropoulos said. "We are hopeless romantics, who do a lot of dreaming. And we both share this great affinity with water, the beach and the ocean."
Because Mr Papaspiropoulos looks much younger, it was two months before they realised more than two decades separated them - and that Ms Tobin's father was six months younger than her partner.
"But love knows no age," Mr Papaspiropoulos said. "There was no obvious difference. I knew she was younger but I didn't know how young. It kind of wasn't relevant.
"If you hear about us or look at our statistics on paper you might form an impression of some sort but when you meet us, that all rapidly disappears," he said. "The stigmas evaporate."
The couple believe they are soulmates and it helps that Mr Papaspiropoulos is young at heart, while Ms Tobin is "an old soul".
Ms Tobin moved in with Mr Papaspiropoulos six months after they met and though she never planned to have children, she became a mother to Alexandra, 10, Max, 7, and Niko, 4.
"It's going to break my heart when Niko goes to school," she said. "I've raised him since he was six months."
Initially there was scepticism from outsiders and when Ms Tobin first told her parents how old Mr Papaspiropoulos was, they thought she must have said it wrong.
But at least half a dozen of their friends have relationships with a 10-year age gap; one woman is 11 years older than her male partner.
Mr Papaspiropoulos, a Greek Kiwi who was raised in Hamilton and Wellington, spent a decade working overseas before he met Ms Tobin, originally from Australia.
The couple returned to Auckland last year with the children and next Friday, they will marry at St Mary's Church in Parnell.
Their union is a one-in-100 event, according to Statistics New Zealand analyst Anne Howard. Of the 61,692 weddings in New Zealand from 2010 to 2012, only 1 per cent of brides were more than 20 years younger than their grooms.
The statistics, which excluded couples who came from outside New Zealand to marry, showed almost a quarter (23 per cent) of couples were less than a year apart in age.
"We tend to marry people close to our own age," Ms Howard said. "They're a special couple."