Reim was born on 26 November 1957 in Korbach, Hessen. He grew up in Homberg. His father was the director of the gymnasium in Homberg. After receiving his Abitur, he began his undergraduate studies in the German and English languages as well as Germanistic and Anglistic literatures in Göttingen. This took 18 terms – this is above average, as he spent its time predominantly in the music studio and not in the lecture-room.