O, Fortuna is a burlesque night club in Pioneer City, owned by its namesake, Veronica Fortuna.

The club is actually a front for the Pioneer City Resistance, as Veronica and most of her employees are part of the resistance.[cast]

The customers are the kind of men you want to keep at arms length: it isn't exactly the kind of place to look for a boyfriend.[c3p14]

Employees of O, Fortuna

Pandora
Zero Angiers
Isabelle Monday
Veronica Fortuna, the owner
Con Yung
Zufolene
Tallulah Zaragoza
Lyra Lujic, the only person who works here who isn't in the resistance, as well as the only straight person on staff.[SemiCanon]

Trivia

There is a mural behind the stage of O, Fortuna.[c3p18] This mural is based on a drawing by Urs Graf, known under the titles "A Soldier Visits the Harlot Fortuna" or "A Mercenary Bribes the Harlot Fortuna."

Swiss Mercenary With a Prostitute (Wikimedia Commons)

There is also a picture of a butterfly on the wall.[c3p4]
It's a burlesque club, not a strip club.[c6p3][c6p4][c11p2]
O, Fortuna is based on a real building at the corner of 400 S and State.[SemiCanon]