The Spain midfielder moved to PSG on a five-year deal last month for a fee that reportedly earned Napoli an initial €21.5million.
Fabian revealed it was an easy decision to make the move to the French capital.
"An offer arrives, between all of us we believe that it is very good, that you could not say no to a club like Paris, for the project they are doing, for the club, for history," he said. "I had one year left on my contract, and both Napoli and I were interested in starting [talks], and I think it was a very good choice."
Fabian is relishing the opportunity to work with the likes of Neymar, Kylian Mbappe and Lionel Messi.
"When you arrive, it's a bit impressive to see the best players together, to know that you're going to change with them that you're going to live with them every day," he said. "It's a privilege. But at the same time it's normal. They're normal kids."
Fabian has plenty of competition to nail down a place in Christophe Galtier's side, but is ready to make his grasp his opportunity.
"They like what I've been doing these years," he said. "At Napoli, due to work or luck, things were going well, as a team and personally. They ask me for the things I've been doing. Order. Being orderly on the pitch.
"In the end I am a player who likes to run, to be up, to be down, and they asked me for that, to be able to reach the area, and then be able to come back, help the team defensively, because in the end we are a very aggressive team that we have a lot of people up top, and in the middle we have to have that solidarity to be able to defend well, compact.
"He [Galtier] asks me for a bit of both: to help them defensively, but at the same time that he can also reach the area."