Bobcat? Or just really big house cat?

When San Jose residents walk around Colleen Pizarev's neighborhood they often pause when they spot a large creature sitting in her window.

Is it a bobcat? Maybe a lynx?

Complete strangers knock on Pizarev's door to express concern that she might be harboring a wild animal. Some have even called Animal Control, though no Animal Control officers have actually investigated the claims.

But it's not some dangerous wild animal, Pizarev laughs; it's "Spock," Pizarev's very large, very friendly house cat.

"He is very unique," Pizarev told CBS News. "But it's not so much him that's unique, it's his breed -- they're all like this."

The 27-pound, 46-inch-long purebred Maine Coon, one of the largest breed of domestic cat in the world, certainly turns heads when he walks into a room.

"When people see him in the window they don't see he has a tail or pointed ears and want to express concern," the owner explained.

The indoor cat's story went viral after a newspaper reported on the cat that makes a "scary" first impression.

"I've been taken aback by the notoriety," Pizarev said. "It's a little overwhelming."

Nearly 4,000 people now follow the cat named after a "Star Trek" character on Facebook after reading his story.

The first thing Spock hears when he walks into a room: "Oh my gosh."

"When people see him, that's what they say," said Pizarev, with an understanding that her cat is larger than most house cats.

Pizarev wants to assure residents and neighbors that Spock is harmless.

Spock is "like every other adolescent."

He's addicted to YouTube, runs around the house and occasionally breaks household items -- like coffee cups.

"He can't control it; he's like a big puppy," Pizarev joked.

As soon as Pizarev hears a knock on her door and a stranger on her porch, she can assume it's about Spock.

"I take the opportunity to explain to them about Maine Coons," Pizarev said. "They do feel silly, start laughing and then it's over."

Although it makes for a funny story, Pizarev hopes Spock's story helps others learn more about the unusual breed.

"They make wonderful pets and they're not scary," Pizarev said. "They're very, very gentle creatures."