Kirst
From Tardis Wiki, the free Doctor Who reference
Kirst was Joel's girlfriend.
Joel was Sallak's cellmate. After their release, Joel and Kirst worked for him. The Eighth Doctor convinced them of Sallak's bad intentions, and that he would pay them a million pounds to help him instead. After they did so, he wrote them a cheque for the amount. (PROSE: Father Time)