1) The Constant Lady
Availability: the Happy Medium side mission
The exact location: The collectible is in the chest on the main floor of the warehouse [South Quarter / Riverside - Eelbiters Warehouse], close to the building's entrance. Watch out for the two enemies in the area.
2) The Virtuous Lady
Availability: The Carnal Connoisseur side mission
The exact location: You need to reach the manor's vault [South Quarter / Riverside - Collector's Vault] and locate the button that will open the passage to the secret chamber. Climb down the ladder and take the collectible from the chest (in the meantime, pay attention to, at least, one opponent in the basement!).
3) The Porcelain Lady
Availability: The Sideshow Attraction side mission
The exact location: At one of the lower floors in the building, there is the locker room [Stonemarket - Watch Station Lockers] and that is where you need to get. Walk around the bandit carefully (it is also a good idea to distract him) and break into the locked chest, quickly, in order to obtain the collectible.
4) The Observant Lady
Availability: The Silence is Golden side-mission
The exact location: The collectible is at the first floor of the residence [South Quarter / Riverside - Oxheart Perry's Residence], in the bedroom. Watch out for the owner of the residence and make sure that you have disabled the trap here (the box is in the wall on the left). Only then, examine the chest of drawers on the right.
5) The Statuesque Lady
Availability: The Hand Tailored side-mission
The exact location: You need to gain access to the first floor of the tailor's [Stonemarket - Alfonso's Residence] and locate the locked bedside cabinet in the bedroom, where the collectible is. You need to watch out because the upper floor is frequented by one of the mercenaries.
6) The Burnished Lady
Availability: The Heartbroken side-mission)
The exact location: The Collectible is on the first floor of the Clockwise's residence [Stonemarket - Clockwise's Residence] (you can explore that place right after the beginning of the mission), in the cabinet.