So, for the sake of this story, let's say that Pouf was born when Pitou caught Kite and that Gon was awake while they were running away, and that Killua and Gon never called Kurapika during the Greed Island Arc. Otherwise this doesn't work. I REALLY want this to work.
Pouf remembered little about his time as a human. He remembered a similar appearance to his current one with similarly colored eyes and a similar posture and way of standing. Yet he remembered a different fighting style and a distinct lack of wings. He also remembered his inability to play a violin despite his current affinity for the instrument. He remembered some things he assumed to be key events in his past selves' life. He remembered receiving a hard plastic card of some significance. He remembered killing a large man who had gray hair and wore a tank top under a jacket.
He also remembered saving two younger boys. A white-haired one and a black-haired one from someone. Who was still unclear to him, but he could tell that all of these memories had had been either precious or extremely impactful to his past-self.
He wasn't even sure of the identities of the two boys. He had assumed they had been his brothers or close friends. He also had vague memories of a man who normally claimed to be a teenager with black hair.
Pouf normally disregarded these things, choosing to focus more on his defense of the king than figuring out who he used to be.
Until he met THEM.
The two boys his former self had saved.
The white-haired boy with the slated blue eyes and the black-haired boy with the round chestnut eyes.
As soon as they saw him, they stopped dead in their tracks on their run through the forest, away from Pitou and Kite.
Both of their eyes widened in great shock, even horror spread through their expressions.
"K-Kurapika?" The black-haired one asked.
Pouf didn't know who this was. Who this 'Kurapika' was. But he knew these boys recognized him, and he vaguely recognized them. He knew he had known them once. In another life.
"I am not whoever you believe I am. I am Shaiapouf, a member of the royal guard" He bowed in his usual elegant manner.
"N-no. You can't be an ant. You're Kurapika." The black-haired one insisted.
"I insist that I am not." Pouf replied.
"Y-Yes you are. You have to be... We haven't heard from him in months..." The black-haired one seemed to have come to some sort of realization.
"No. Never mind. You can't be Kurapika. He never would've been caught. He'd have fought until every single one of you ants was dead before he let himself be caught." He contradicted himself.
Then Pouf was quite certain of his link to this 'Kurapika.' Most likely, Kurapika had been his name as a human and these boys had known him as a human. And when these boys knew this Kurapika, he was a very powerful warrior.
Then a flood of memories rushed through Pouf's head.
The entirety of the Hunter Exam. Going to retrieve the White-haired boy from his family. Learning Nen from his teacher. Fighting the Phantom Troupe. Killing Uvo. Saving them from the other members of the Troupe. Getting ill and eventually leaving without saying goodbye. Getting caught by a Chimera Ant while visiting NGL for work. Trying to fight back, and failing.
Then the names.
Netero, Tonpa, Hisoka, Hanzo, Pokkle, Ponzu, Illumi, Zeno, Canary, Uvogin, Pakunoda, Chrollo, Melody, Leorio, Killua, Gon.
These boys were Killua and Gon. Two of his three best friends.
Two of the three people who had saved him.
That had stopped him from losing himself.
And he had never said goodbye.
Kurapika had never said goodbye.
He had told Leorio to say goodbye for him. Say that they would be fine. That they would meet again.
Kurapika hadn't planned an eventual meet-up like this.
Not for his friends.
"I have great friends" (That quote is most defiantly wrong, and I'm very sorry for that)
"You are Gon and Killua."
They moved their heads up in what seemed to be a new kind of surprise.
"And you were great friends." Pouf stated before beginning his attack.