First, when you say the private part, I assume you mean her genitals or her breasts? Yes, those are very sensitive (not "weak"). BUT, most women respond to kindness and love before they feel sexually aroused by someone. A person who just focuses on the "private parts" is not going to make that woman happy, since she is more than just her body. She is also a person.
An "Achilles heel" is a person with a weak spot.
a person's "achilles heel"
Weak
Yes, they built a weak central government.
weak!
The weak part of a girl is her private partThe weak part of a girl is her private part
he has a weak spot for red heads
After bathing in the River Styx his "Achilles Heel" or weak spot was his underarm.
terds
his weak spot
Achilles' heel was his weak spot thus the saying that someone's weakness is their "Achilles heel."
In the crust the weak spot we have is the Magma Chamber. But, deep down to the mantle such weak zone is the Asthenosphere.
The weak spot of an alligator is it's somach
his pride
Stomach
terds
His heel