A mask of some sort that is available for purchase from a fancy dress store or other such sordid establishment. It resembles a dog and is worn for the act of sex (violent, coprophillic or otherwise). The sexual craze of the "dog head shag" was started during the first decade of the twentieth first century by dog-head fanatic and frequent mule molester Maisie Jean Denning. Denning was obviously a sexual pervert due to her grandfather's illicit sexual activities with a painting of large lips in the Ikon Gallery Birmingham. Denning would attack men of all shapes and sizes and force them to wear the dog head mask. Then she would copulate with the poor victim whilst forcing him to woof and referring to him as "JJ" or "Flash".
Denning's dog head fetish was sparked by an incident on a bus whilst going past a fancy dress store that had a dog head mask in the window. And also because Denning loves big red dog.
"If only there were a dog head like Flash's... I would not have any problem climaxing then"
GIRL A. "Jeez... you're the best sex I've ever had! No ones ever done the dog head so well"
"Dear Deidre, I don't feel like I am pleasuring my wife anymore, please help. cum2quickchris."
"Dear cum2quickchris, why not try a dog head? Girls go wild for that nowadays"