The technical term would be female genitalia.
An attraction to cunts is useful. All females have one. And, if and when you get to bed with her, it would be useful if you found her cunt sexually attractive.
Details of Training
Your basic choice for training pictures is attractive females showing their cunts. If you have no attraction to cunts, you should start with Beginning Training.
Your basic choice for "distractor" pictures is beautiful naked women not showing their cunts.
Clitoris or the Inner Labia
A specialized training is to target just the clitoris. You would excite yourself when pictures included the clitoris and not excite yourself when they don't.
The inner labia, also known as the inner lips, are the two flaps of skin surrounding the vagina and clitoris. Some women have a long enough inner labia that it protrudes even when the outer labia are otherwise closed.