If you really like the girl, you wouldn't bite them. I mean, think of how the girl feels if you hold her
best way to kill a romantic mood is when she looks at the hideous site. Even though biting has a good feeling, it's not worth it. This being said, I quit cos I work at a fast food joint and prepare vegetables on a daily basis... Let me tell you, a nail is really handy protection against knives. Saved my skin twice... when I bit my thumb nail about a couple of weeks ago, there wasn't much protection against my skin while cutting some cabbages and I got a really deep cut. Two important lessons, dont bite nails if youre in fast food/food prep and concentrate on the blade 
hope it helps