Tatiana "Tania" Romanova (Daniela Bianchi (voiced by Barbara Jefford))’s Timeline and Summary

Tania's recruited by Klebb to seduce James Bond.
She sneaks into his hotel room and hides naked in his bed.
After a passionate night together, she tells him the whereabouts of the Soviet's Lektor machine.
Bond steals the machine and the girl and flees Istanbul.
Tania seems enchanted by the prospect of having a British identity, so somewhere along the way she starts to play housewife.
She's mostly unconscious while Bond deals with the assassin, Grant.
In Venice, Tania proves her loyalty to Bond by shooting Klebb dead.
It's on to happily-ever-after with 007, which probably means up until his next assignment.