Green’s Dictionary of Slang

falling den n.

[SE fall]

(US black) a bed.

[US]H.W. Odum ‘Folk-song and Folk-poetry as Found in the Secular Songs of the Southern Negroes’ in Jrnl American Folk-Lore July-Sept. 284: What’s stirrin’, babe; stirrin’, babe? / Somebody in my fallin’ den –.