While many may try to cover them up by wearing tights, this doesn't always work. Is the tattoo showing through a problem or a fashion statement? There are arguments for both!
Many people want to get 999 tattoo meaning so they can show them off. But, this isn't always appropriate. While you may love your tattoos and be admired for them in a social setting, in a conservative workplace they may not be so welcome. They can look very unprofessional and won't bring you the type of respect that you'll need if you want to get on with your career. In this instance, tattoos showing through tights would most definitely be a problem.
The way to avoid this would be to wear opaque tights rather than thin pantyhose, the thicker the better. If you need to make a good impression, you shouldn't let even the slightest hint be showing. As long as the tattoo doesn't show through, you can get on with your day safe in the knowledge that you look professional, but all the time knowing that you've got a cheeky side just waiting to be revealed.
However, in places where the look doesn't have to be so professional or in social settings, tattoos showing through tights can definitely be a fashion statement. People who admire tattoos will undoubtedly shoot you a few admiring glances, and if there's no reason to hide them you can get them out with pride.