Some dommes have a love of making their submissive slave do whatever they want them to, and for some, that means enjoying a little feminisation. In the world of BDSM, feminisation is when a dominatrix will switch the role of their sub, usually the male submissive, to the other gender. Because many submissive slaves are male, this means they will be female. They will give them an appropriate name and use cross-dressing to help them with the role playing aspect of the fun. They will get them to use more feminine phrases and body language, and the sub will be encouraged to take on their new role as much as they can.
Costumes and outfits are often very domestic, and many have lingerie on underneath the clothing. Some like to take it a step further and try on some leather or latex, which will hug their figure and please their mistress. Sometimes, an outfit can simply be high heels, a lacy bra, and some panties. Other times, your dominatrix might force you to slip into a sexy nurse or maid costume for them, making feminisation the ultimate BDSM tool for those interested in humiliation.
Your name may be feminised to keep up the fantasy, or you might be given a new name while you are with your dominatrix. They will call you by this name, sometimes even referring to you as a sissy, a princess, or a good girl if you behave in the way they want you to. You might also experience pegging, as your mistress will make you the 'woman' in this situation, or they might decide that the best use for you is to please others. They might get you to perform oral sex on another male and reward you for good work. Begging and pleading can become a part of the fantasy as well, as can using a higher pitched voice.
Feminisation is a form of humiliation that many find to be a huge turn on. They love this kind of BDSM, as they get to experience how the other half lives and to enjoy things that they enjoy. You might want to give yourself over to your chosen dominatrix completely, and if so, this is just the thing for you. Often, it can be tied in with chastity control, and so you will not get to enjoy an orgasm, unless your kind dominatrix lets you.