The worst part of a BJ is when she constantly touches your penis with her teeth
But there are also abilities for a female to show in normal sex, especially when she's on top. Plus some other, as imagination for the foreplay, the seductive way of whispering, teasing, etc.
If you have a girlfriend just giving a pornstar+ type BJ every time, without the other erotic ingredients, you'll look for someone else anyway for a LT relationship.
Damn, if she's not perfect she's not good enough
