In the IT world we talk about "lusers" [sic].
By comparison, the "SLF" moniker for customers is positively respectful, implying that pax can actually get on to the aeroplane under their own steam. Lusers, on the other hand, can't understand why their computer isn't functioning during a power cut...
I hope the "25F" handle makes it clear whereabouts on the aircraft I'm to be found...