Nearly 15 years. That's how long she has known James Z Maguire.
And it had taken her 6 years to realise what she felt for him. By then they were full-fledged adults, expected to know everything they were going to do in life.
The years following 23, were filled with tears and laughter - as Erin and Orla's granda had a heart attack (and didn't make it). Michelle lost her mind when she found out Take That had gotten back together. The lunar eclipse of 2007 drew the entire group out of Clare's flat watching it as the shadow of the Earth covered the moon, dusting the moon red.
And now it was 2009. As they neared Anna Quinn's 18th birthday.
Everything was being prepared for the youngest Quinn daughter's birthday, and it took everything back for Erin - remembering her own, somewhat, disastrous party.
Erin smiled from the sidelines as Anna pushed the banner higher and higher with her words as their father struggled on the ladders. "It's the highest I can go, love," Gerry called to his youngest.
"Takes you back, doesn't it?" Came the voice of James, who nearly made Erin jump out of her skin. The curly haired now man, had grown into his features and his unruly hair.
The group didn't get together as often as they used to with jobs and actual families - in, surprisingly, Michelle's case - taking most of their time.
Erin had finally become a published author, despite Michelle's complaints about the romance novels, they were actually fairly sweet. Whenever she worked on her novels, she imagined the characters as her and James.
Clare had become a lawyer. A fairly successful one, winning most of her cases as she refused to represent anything to do with murders.
Orla was a step aerobics teacher at the dance hall in Derry, having moved into the house next door to her ma's, who still lived next door to Gerry and Mary.
Michelle was still at Dennis' little shop (but it had more or less been handed over to her, as Dennis was getting closer to retirement), whilst also being a single ma to her little girl, Deidre Junior - with the nickname DJ.
And finally James, he was a budding filmmaker - not Hollywood big, he was becoming well known in the United Kingdom.
The entire group were happily dancing on the floor, Erin watching as Anna and her friend group stupidly danced to the music played by the DJ.
Michelle was dancing around with DJ, and Orla was dancing around by herself. Clare was dancing with her girlfriend, as Erin was spun around by Gerry.
When Gerry spun her out, he let go of her hand and sent her spinning into James' arms.
"Hi," James smiled, holding Erin by her waist.
"Hi," Erin replied, gripping onto the sides of James' shoulders.
They were silent as the song finished, and was changed to Proud Mary by Tina Turner. Which took James and Erin back to the joint birthday party of 1998.
"Still remember it?" James asked about the dance moves they pulled, which were living forever in his mind.
"Yeah," Erin said, but before James could drag her onto the dancefloor. "James, can I talk to ye? Outside?" Erin asked him.
James nodded, only a little bit scared - because the last time Erin talked to him outside, she told him to move on (which he never truly did, only going on a few dates ever since and neither of their relationships lasting longer than a few months...)
The door closing behind them, both James and Erin's hearts were in their throats.
"What is it?" James asked, fiddling with his fingers, waiting for Erin to talk.
She looked up at James, was about to speak - when the butterflies overcame her again, but it wasn't followed by the terror. She continued to stare up at him before she took him by his face and kissed him.
James was stunned for a second, before kicking himself and responding. It had been a long time since he'd last kissed someone. And even longer since he'd last kissed Erin.
When they pulled away, James rested his hands against her face. "What was that about?" He asked, tucking a lock behind her ear.
"I don't want to wait anymore," she tells him and watches as James' eyes widened and started shining with unshed tears.
"Really?" James whispered, shuffling closer to her, as his forehead pressed against hers.
She nodded, and James kissed her again. His biggest dream since he was 17 coming true. Hopefully, he had won the heart of his dream girl.