Voldemort and his Death Eaters are increasing their terror upon the Wizarding and Muggle worlds. The wizarding world exists parallel to the Muggle world, albeit hidden and in secrecy. Wizarding banks provide money-changing services for those with Muggle currency. Muggle Studies is an option of study at Hogwarts. Rowling said during an October 2007 book signing that Cho marries a Muggle. Albus Dumbledore has expressed interest in Muggle knitting patterns and ten-pin bowling. The spell was cast after Riddle murdered a Muggle tramp. Arthur works for the Ministry of Magic, initially in the Misuse of Muggle Artefacts Office. Magical brooms are mass-produced, with new models coming out regularly, similar to muggle cars. The term "Muggle" is sometimes used in a pejorative manner in the books. The book begins with a scene involving the Muggle Prime Minister.