The actor also revealed that director Edgar Wright always had him in mind as the male lead on the project.
Cere told Teen Hollywood: "It kind of fell in my lap, really. I was just in the right place at the right time. I had a meeting with [producer] Marc Platt about it, I met with Edgar, and he was really enthusiastic about me being in it, which was amazing.
"It’s so nice to hear that from a director you respect, that they want to work with you. And I loved the graphic novel too, so it just presented itself and was just an amazing opportunity."
Scott Pilgrim Vs. The World is currently playing in the US and arrives in UK cinemas on August 25.