In inveterate nail-biter, I decided to quit in my early 20s. I cut my nails now when they're too long. But I hate jagged edges (one of my many OCD traits that led me biting in the fist place), so I finish up with a nail file. It makes me look like a girl, but the power of OCD is overwhelming :$
I understand that... I've got a thing (whether it falls under OCD or not, I've no idea), where I don't like rough skin on my hands. I've got eczema and that flairs up from time to time, usually on my fingers and I hate the feeling of rough or pitted skin that can cause, to the point where I'll pull scabs off, bite any tiny loose bits of skin away and shave my knuckles.
I have to do Emily's nails too. Fiona cuts them too short (one of Emily's OCD traits is having white at the ends of her nails). And then file, because like her old man, Emily has sensory issues.
Indeed. I suspect that nail clippers and files are an affectation of the modern white-collared classes, and nipping down to Boots to buy same never occurred to the horny-handed sons of the soil in the Middle Ages. We're all faggots. Except you.