Obsessed? Just a little. But that made it an easy decision when Marvel came knocking, asking if Insomniac would be keen to work on a big budget video game adaptation featuring one of their characters.
But which one? Faced with choosing from more than 8000 superheroes and villains, it couldn't have been easier.
"Of course it was Spider-Man," says Stevenson. "He fits us the best. We tell underdog stories, he's all about traversal in an open world ... the decision took a few days."
Then came the hard part: getting it right. Stevenson says the team at Insomniac agonised over every little detail. "It's corny, but with great power comes great responsibility. He's one of the world's most beloved characters, like Mickey Mouse beloved."
Next came the story. "You have 50-plus years of comics, six movies ... there's a lot of material," says Stevenson. So which one? They settled on the theme of worlds colliding, as Peter Parker battled to balance his dual lives.
Then came the webslinging. To do a Spider-Man game properly, he had to be able to swing through the streets of New York. "If it's not right the whole thing falls apart," says Stevenson. "You'd better be able to websling, and it better be really fun and exhilarating. We started working on that on day one." He says it took a year and a half to perfect.
But then came the tough one: finding someone who could play Peter Parker. "It was really hard," says Stevenson. "No one can tell you what Peter Parker should look or sound like, but you know it when you see it or you hear it."
After dozens of auditions, they decided they needed two people: one providing his voice, another his face. "He can be awkward and stumbly, but he can be Spider-Man, so he's sort of cocky, making jokes [but] on the edge the whole time. Trying to find someone who can embody those different moments was critical."
Now it's out, Spider-Man has received overwhelmingly positive reviews, with many suggesting it among the best games of the year. "Probably the best Spider-Man game ever done," said IGN.
Being the giant fan that he is, with an acclaimed video game based on the character under him, Stevenson is perfectly placed to answer TimeOut's final question: why does Spider-Man have such sticking power?
He doesn't pause a beat. "He's that classic underdog," says Stevenson. "Things don't always go right for him [and] he has too much on his plate, just like we all do. He always has a relatively good sense of humour about the whole thing.
"He's every man. You know him, you could be him and you could see yourself in those situations. That's why he's so popular."
• Spider-Man is out now on PlayStation 4.