Biography:From Wikipedia, the free encyclopedia. Gene Simmons (born Chaim Witz; August 25, 1949) is an Israeli American rock bassist, singer, songwriter, musician, actor, and businessman. Known as "The Demon," he is the bassist/vocalist of Kiss, a hard rock band he co-founded in the early 1970s. Simmons was ranked number 12 in Roadrunner's list of 50 Best Frontmen in Metal History.