。
What a contrarian that guy is.
Literal
What-a perverse guy is.
なんて (what a!) is an exclamatory marker expressing surprise or exasperation. つむじ曲がり (contrarian/perverse person — literally 'twisted hair whorl') is a vivid, somewhat old-fashioned character description. やつ is casual and slightly rough for 'that guy.' A punchy exclamation.