Rosa Klebb is the Eastern European proprietor of Klebbs Fine Jewels. After being robbed by a man with a melting ray, and having over seven figures in precious stones stolen, she asked the Middleman and Wendy Watson to provide her with the name of the thief. She made no request for the jewels themselves, or for the thief to be arrested; this, combined with an associate of hers wielding a baton, suggests she had her own less-than-savory plans for the thief.
Though she denied it twice, the Middleman strongly suggested Ms. Klebb was a former KGB operative.