Sorry, pal. No tux, no entry!
― Rajan's doorman[src]
"Ballroom Dance Party" was a job for Sly Cooper in "A Starry Eyed Encounter" of Sly 2: Band of Thieves. The goal was to infiltrate the ballroom and score a dance with Carmelita during the heist.
Upon knocking on the door to Rajan's ballroom, Sly was greeted by the doorman, who explained the party's dress code regarding the need for a tuxedo. Since Sly lacked one, he was denied entry to the ballroom. Bentley contacted him, however, suggesting he would probably find a spare suit inside the guest house.