This achievement is Dancing Queen: Dance for Vogga, a Hutt crime lord operating on Nar Shaddaa.
A female Jedi Exile can dance for him as the first step towards robbing his treasures. A male Exile can have a companion dance for the Hutt instead. I don't know if Male exiles can earn this achievement.
The dance recruiter is in the cantina, across from the Pazzak Den. You may need to use force Persuasion to convince him to let you dance.
This achievement is Buggy+, however. I earned at the time I completed
with a female exile.