Green’s Dictionary of Slang

rob my pal n.

[rhy. sl. = gal n. (1)]

a woman.

[UK]J. Franklyn Dict. of Rhy. Sl.
[UK]Partridge DSUE (8th edn) 981/1: rob my pal. A girl [...] modern version of Bob my pal.
[US]J. Burkardt ‘Rhyming Sl.’ Wordplay 🌐 rob my pal gal.