Brian Lagace, 21, of Orillia, and a 24-year-old American were found entwined on a bed in a downtown Toronto hotel.
The Chicago man had been undergoing a sex change.
Police believe Lagace, a computer whiz, had posted an ad on the Internet saying he was looking for a woman to spend an evening with -- a night that would end with a double suicide.
The man from Chicago responded, signing his messages with the names Shelly or Michele.
Lagace's brother, Paul, said he is still struggling to make sense of it all.
"It's like some really demented Romeo and Juliet", he told the Orillia Packet and Times.
"There's no way Brian would have known it was a man. The police didn't know until they did an autopsy."
Paul Lagace said his younger brother had become obsessed with suicide and spent hours on the Internet talking to strangers about self-destruction.
"The thing he wanted to do was die in somebody's arms. He was afraid of dying alone. He tried to kill himself a couple of times. He always talked about suicide."
Over the past few years, Brian Lagace became very cynical, his brother said. After a long relationship with a girlfriend ended, he quit his job at a computer shop and became very gloomy.
"He cut everybody out of his life."
He said he doesn't blame the Internet for his brother's death: "He was going to kill himself anyway."