Imp turned into seducing looking woman, and marine dropped the weapons and gave in.. expecting demonic encounter. Later to discover that it was actually male imp pretending the woman (women clothes, make up, etc.. you know). He shot the imp 'on sight' however, even though it maybe was little too late. Since then, he got +1 circumstance bonus to accuracy and damage against imps.
Joking of course.. it was not the the imp but demon.