It is definitely an outdated, even laughable idea that female back tattoos are for only the "loose" ladies and particularly thinking of the lower back tattoo as a "tramp stamp". It is extremely close minded to think that an attractive woman with a back tattoo must be immoral and unsatisfied. It's very much the other way as a woman who is strong, independent and fashionable is one who would strongly consider a female back tattoo.
There also is the upper back tattoo which is highly popular. These tattoos can range form a simple small and delicate design such as a flower to a large and elaborate design. Similar to the lower back tattoo a high back tattoo should be placed in a way that it can be covered when appropriate. However the upper back tattoo may be more difficult to cover up when formal dress wear is common. A gown for example would usually be lower cut around the upper back making it difficult to cover your design. You might consider a smaller design that would better
blend with this type of formal wear and actually add to the attractiveness of your look. It does seem that the social bias of tattoos is fading and therefore some female back designs might be admired in this setting.
