There’s nothing about wanting to be dominated that’s inherently unmanly. When you stop and think about it, seduction is a dominant act we often associate with women, while being seduced is certainly the more submissive role.
Of course, we often associate that with men.
But before you talk to your girlfriend about your requests, it might be helpful to think about exactly what you mean when you say “dominate.” Are you talking about her spanking and yelling at you? Or would you like her to initiate sex in a demanding way, or take charge during the act and spend more time on top or pulling you into different positions?
The more specific you can be with her, the more likely it is she’ll know what you’re looking for and be able to please you. Plus, if the word “dominate” makes you feel uncomfortable, this way you won’t have to use it.