BOBFOC

n.

Heard in Sligo, Galway and Dublin

Body Off Baywatch, Face of Crimewatch. An attractive body paired with an unattractive face.

In use

Yer wan over there looked great until she turned around and I got a look at her face; she's a right bobfoc.

Posh English

That young lady appeared quite delightful until she turned about and revealed her visage, she is a dreadful mismatch.

Same phrase, other counties