A thirster after blood.    From Wordnet, Princeton University. 

Noun : They almost died of thirst. ,a thirst for knowledge.    From Dictionary.com. 

His countenance was the fiery laugh of a thirster for strife.    From Wordnik.com.  [The Tragic Comedians — Complete] Reference

"What are we doin 'here, anyway?" roared some thirster for information.    From Wordnik.com.  [The Clarion] Reference

That thirster, though he lived aft, was compelled to do the work of a common sailor.    From Wordnik.com.  [A Son Of The Sun] Reference

What made him so acrimonious does not appear; he was by nature no thirster for blood.    From Wordnik.com.  [Lives of the English Poets : Prior, Congreve, Blackmore, Pope] Reference

What made him so acrimonious does not appear: he was by nature no thirster for blood.    From Wordnik.com.  [The Works of Samuel Johnson, LL.D. in Nine Volumes Volume the Eighth: The Lives of the Poets, Volume II] Reference

Having then, in a few well-chosen phrases, discussed one type of camouflage, I would pass on and lead the thirster for information still farther into the by-paths of knowledge.    From Wordnik.com.  [No Man's Land] Reference

That fiery thirster after sovereignty.    From Wordnik.com.  [The First Part of Tamburlaine the Great] Reference