Green’s Dictionary of Slang

dooflus n.

also duflus
[? Ger. doof, stupid]

(US black/teen) a foolish, unsophisticated male.

[US]Current Sl. V:3 6: Duflus, n. A clumsy boy; a rustic.
M. Gribble (con. 1961–75) Ten Go In 12: When the E4s and E5s decided it was time to razz a peckerhead, they always referred to him as ‘dooflus’.