Libra and Pisces joins two of the smoothest and most easygoing signs - at least as seen from the outside. The main merit or fascination of this combination derives from the planets ruling the signs. Neptune, the main ruling planet of Pisces is considered the higher "octave" of Venus, Libra's ruler. What this means is that many of the traits of Venus are believed to have their more "evolved" or abstract equivalent in Neptune, and this creates an alluring bond between the two. Yet beyond this, we are dealing with signs that have no tangible way to connect outside of the merely sensual, arty or romantic. It may be that the dream of the partner remains strong, but is finally unveiled to be no more than a mirage. Libra can charm their way out of most troubles, but Pisces senses early on if something is wrong.
More to the point, these two romantic, pleasing and charming characters should have no problems getting along in a less serious kind of relationship. It's at the deeper levels, as is so often is, that their differences show. Libra is highly intellectual and morally aware. Pisces is dreamy, emotional and empathetic. Libra needs to categorize things and deem concepts and behavior either fair or unfair. Pisces is open and floating and often refuses to give judgements or reviews of people and things. They are certainly attracted to the sensuality and soothed by the projection of each other, but frictions may be continually hidden deep below the surface until it breaks free and the two wonder what they at all had in common to begin with. If there are strong bonds by moon sign or planets, this could be a very rewarding relationship. If not, it is likely to fade away.