Nøkk joined Quint's team as a result of their very first crime.
Quint thinks that's a fairly funny way to start what is otherwise a rather sad story, and begins it that way around trusted friends. They also like to throw in that, technically, this whole ordeal was the first thing they did as an Ace Trainer. It was
even the very first day of their adventure across Galar, because of course it would be.
Having recently earned their Ace Trainer certification, Quint had chosen to leave their home in Circhester to participate in the Gym Challenge. However, they decided to spend their first day away from home in Hulbury - thinking their small team may appreciate a beach that was actually
warm. While there, Quint was approached by a man on the edge of the shoreside market who claimed to have a rare and powerful pokemon available. Thinking it may be best to add another pokemon to their team before starting the challenge, Quint followed him to the docks where he revealed a cage with a pokemon inside.
A
cage. Quint saw red at that alone, until they realized the pokemon inside was none other than a Popplio - Nøkk, to be specific. As a recently certified Ace Trainer, they knew that certain pokemon were so rare and vital to their environment that catching them was restricted by certain rules and regulations, and that Popplio's entire evolutionary line was on that list. On top of all of that, Nøkk looked so... sad. The man had his cage covered, and he shrank away from them when the man lifted the cover for Quint to look inside. Even if this man
had ethically caught the poor pokemon, he wasn't treating him right. Quint decided there and then that they would get Nøkk away from him.
After talking more with the man, Quint learned that there
was a fine for catching pokemon in Popplio's line during that season, but that he had captured Nøkk because he "wanted the kids starting their Gym Challenge to have good pokemon". That, and he hadn't
actually caught him - transporting him from net to cage without catching in a pokeball - and that Quint could pay ₽20,000 for the luxury of having such a rare pokemon and catching it in their own pokeball.
Quint kindly declined.
That night, Quint snuck back to the docks. Luckily, the man hadn't taken the cage, instead leaving it covered and behind a few crates. Nøkk woke up as soon as they moved the tarp, and looked at them so fearfully that Quint instantly lost all of their bravado. Stammering, they explained that they were there to help, and that he would need to be quiet. When it seemed Nøkk understood, Quint released
Aphrodite and had her use Fury Swipes on the cage bars until they broke. It took some coaxing to get Nøkk to allow Quint to hold him, but soon enough the poor pokemon was scooped securely in the trainer's arms and taken down to the beach. There, Quint released him back into the wild; they knew that Popplio wasn't native to Galar, but still hoped that he would somehow find his way back home. They watched him disappear under the water and as his silhouette faded away on the horizon before returning to the hotel.
They could hardly sleep that night.
Whether it be nerves about the Gym Challenge or concern over Nøkk, Quint found themselves on that very same beach early that morning. There, they saw a flash of deep blue amidst the rocks. Fearing the worst, they approached, finding Nøkk cowering between the rocks. He cried out when he spotted them, surging out of the water and up to Quint to barrel into them and cling to their leg. Quint could swear he was sobbing.
They will never know for sure what happened that night. Maybe Nøkk realized how far away from home he was. Maybe a bigger pokemon attacked him. Regardless, the Popplio wouldn't leave their side - not that Quint was trying to make him, after that. They did their best to soothe him, and when he had calmed down some, Quint offered to catch him. They could hide him from the man that way, and take him with them easier. They would carry him along until they had earned enough money in the Gym Challenge to take him back to Alola and find its family - or at least, until they could think of a way to convince an adult to do it for them. Nøkk agreed, and Quint caught him in a Premier Ball right there on that cold morning on the beach.
For the next few weeks, Nøkk travelled with Quint and their team throughout Galar. He was especially fearful of humans back then, and thankfully had no problem staying in his pokeball most of the day. Still, Quint would release him with their other pokemon every night or whenever they were camping, and it was in that time that Nøkk grew close with Quint and the rest of their team. Taking care of him and his episodes of depression and anxiety helped Quint become more compassionate, and while Nøkk was never afraid of the trainer after that first night, he grew to see them more and more as a kind of surrogate parent as time went on. Eventually, he even took an interest in the battles he saw Quint training for with their other pokemon, and asked to start training too. This led to him forming a sibling-like bond with Quint's team, and even officially joining their team and taking on the Gym Challenge with them - once Quint had filled out the proper paperwork of course.
At some point shortly after Nøkk evolved into a Brionne, it came to light that the man who had captured him had taken him from his colony before he had the chance to learn their song. Upon learning of this, Quint, Aphrodite, and the Toxel Quint had received from a friend worked on creating a special song for their team (with Aphrodite and the Toxel both already feeling the more musical urges of their later evolutions, and Quint wanting to encourage and help their pokemon). What resulted was perhaps a bit more... metal than what a Primarina's song may usually be - with Nøkk's haunting falsetto, Aphrodite's rich roars, and the Toxel-turned-Toxtricity's electrifying instrumentals with Quint's supporting bass - but was wholly the culmination of the family Nøkk has in Galar.
Despite their rather... unusual meeting, Nøkk and Quint are quite close as pokemon and trainer. Quint still offers to take him back to his family, and at the very least still plans to take him to Alola when they can, but Nøkk is quite happy with the family that found him.