I'm of the opposing view regarding the hyphens, but let me mention this first. Though it might only be one character who uses these initialized expressions, if no other character uses the same combination of words--fully written--in this day and age I'd question (at first) whether the writer was just being lazy like folks writing a text. Yes, I suspect they'll eventually get it, but you risk an initial negative reception until they do...In my opinion.
That said, I disagree with the non-hyphen camp. Think about it, each letter is separately spoken, L, O, L / eL, Oh, eL. If I use the acronym FUBAR, I don't speak each letter being an acronym, so LOL--whether 'we' all know better or not--then falls under the question of 'is it and acronym or initialism?': LahLL, or eL-Oh-eL? Again, we all may 'know' better, and even the reader might, but how often do you find yourself looking up some new internet initialism? There will also be those who don't know (I used to chat with folks online who though able to read English, had their own languages terms for 'hehe, LOL, wtf,' and so on)...and those who simply want to be hardliners and argue the point.
So, I say hyphenate: L-O-L since that is how the character is speaking it, connected as a single initialism, but separate letters.
To push that further, if you were reading off Morse Code in your manuscript, or someone spelling out something, would you:
HELLO, H E L L O, or H-E-L-L-O? Past that, the hyphens connect the letters informing us (in this example) that the letters are connected forming a word...Granted, that argues against my opinion, but one situation is not the same as the other so the rule (in my mind) wouldn't apply.
Lastly, I ran into this issue quite a bit in my current work. My protagonist, Reaper-379, is often referred to in dialogue as '
379.' I don't want to clutter the text with "Three-seven-nine, hold still...", or worse as some suggested, "Three hundred, seventy-nine, hold still..." So, I left it as numerals. HOWEVER, I don't want folks
thinking, 'three hundred, seventy-nine' as they sound it out in their heads. So in dialogue I write it "3-7-9, hold still..."
I have so many characters and places in my story that have numeric or alpha-numeric designations, I decided to use the system throughout for consistency...and boy does it clean up the text a LOT (that's 'lot' with emphasis BTW, not L-O-T
)
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