The Collaborative International Dictionary of English v.0.48:

Debaucher \De*bauch"er\, n.
   One who debauches or corrupts others; especially, a seducer
   to lewdness.
   [1913 Webster]

WordNet (r) 3.0 (2006):

debaucher
    n 1: someone who assaults others sexually [syn: violator,
         debaucher, ravisher]