"Slimcea Girl" took its title from Slimcea, a low-calorie bread sold in the UK during what has been reported as either the 1960s or the 1970s; the "girl" was one featured in the Slimcea TV ads, which featured a jingle inviting the viewer to be a "Slimcea girl". Another inspiration was Julie Christie's character in the film version of "Billy Liar", whom Virgo described as a "liberated" "It girl", saying, "I just found it a powerful image". The song has been called "a cynical stare at the dreams and fantasies of those people who live behind the blinds Suburbia)"; musically, it has been described as reminiscent of Burt Bacharach, gospel music (in its use of backing vocals arranged like a choir), and "a Tamla torch song".