The past history of this incarnation of Benjamin Grimm most likely mirrors that of his Earth-616 counterpart, up until the moment that Sue Richards became pregnant with her second child. However, her other child, Franklin predicts that the child is a monster, but no one believes him.
During the course of her pregnancy, Sue's physical condition worsened daily and took a horrible toll on her. She became weaker and weaker and almost becomes skeletal, losing her invisibility powers. When she gives birth to her child, Sue died in the process. The baby turns out to be a monster, who had possessed its body as Franklin predicted, a succubus (from the Negative Zone) who drained the life energy of others. In fact, she drained Susan's life while she was still an unborn baby in her mother's womb.
Reed named the baby Suzy in order to deal with the loss of his wife. As the years go by, Susan slowly killed more and more people, and eventually, Ben also fell victim to her. Since he was mutated by cosmic radiation, the drain on him took longer, and it finally manifested when he lost his powers, which he actually considers a blessing since he was now human again.
One night, Ben went out on the town with a lady friend, he came across a mobster he once clobbered who wants revenge. The mobster gunned him down on the street, and he was rushed to the hospital with his friends and family soon joining him there. Even though it was possible that he can pull through, it was all for naught when Little Sue visited him with glowing red eyes and drained away the last of his life force, killing him.