The new contract for the 24-year-old, who played over 100 games for Easts Tigers in the Queensland Cup, is for three years in total.
“They offered me a new contract for another two years,” Torpe told BBC Sheffield.
“I love the place. They’re a really professional club. I believe they’re going somewhere with the new stadium.
“Mark Aston’s coach for a few more years, and I want to see where they’re going, and I’m happy to be part of it.
“Once I got here I realised how good a place it was, and how professional it was.
“They gave me the offer and I grabbed it with arms open.”