Oblivion:Gweden Recruits (and other quests)

Cleavage in all directions
Cleavage in all directions.

Recruit at any time

Dependent on Main Quest progression

By request only

Tsarrina will tell you when it's time to do these quests.

Requires Shivering Isles

The SI expansion for this adds two more girls, whose quests run consecutively.

There is another quest that requires SI, but does not result in recruiting anyone. That concerns Miranu, the cousin of Silanu and Falanu, who is an advanced Alchemist with her own secret laboratory, (and perversion).

Quests depending on other questlines