The twins known as the Tonnika Sisters are reknowned for their beauty, something which has saved their lives quite a few times. They come from the planet Kiffex, and from a young age learned how to swindle money out of people. As children they did not have any role models, since they were abandoned. They were taken in by a Kiffex colony, but escaped when a stupid young scout laned on Kiffex for fuel.
They entered the galaxy, and found that there was much more money to be had than just the pathetic pickings they had scraped on Kiffex. Being twins, they both went by the name Bresenni when they were conning people. This meant that their victims did not know thatthere were two of them, and more often than not the victims would not realise until they had lost all their money and valuables. But one day they would be bound to scam the wrong person, and they did.
Grand Moff Argon was not a forgiving man, and when he had been conned out of 25,000 credits by Brea and Senni, he sent men to scour the Outer Rim Territories to find them.
Running from the Moff, Brea and Senni continued to work their way through the wallets of the galaxy, and also did smuggling missions for Jabba the Hutt. It was on one such mission that they met Han Solo. Han was overcome by their beauty, but had heard all about them and so kept his credit belt where he could see it. After he had been talking to them for a while, he decided to play a little trick on Lando. He told the girls to play Bresenni, and to woo Lando. This worked perfectly, and Lando, oblivious to the fact that there were indeed two women who made up Bresenni, fell for it. In the end he fell in love with Bresenni, and the night he was about to ask for her hand in marriage, he received a hologram cube from Han, letting him in in the joke. Lando laughed, but vowed to get his own back on Solo.
The twins went to Tatooine a few years later, where they had managed to get invited to Jabba's seven week party. They knew it would be perfect for casing new victims. But unbeknownst to them, there was another pair of sisters on Tatooine at the same time. These women were pretending to be Brea and Senni, and were in the Mos Eisley Cantina looking for a pilot. But there were arrested when Imperials came in, some of whom were working for Grand Moff Argon. They managed to escape with the help of a Rebel spy, and left Tatooine.
Meanwhile, the real Tonnika Sisters were at the party having the time of their lives. Afetr that they attended many more parties, and found many more wallets.