Strange experience with bondage what do you think?

[Man]

Last week me and my girlfriend were in the middle of sex and we played with some light bondage. The strange thing is she tied me up and then put her tennis skirt on me really high, and forced me to wear a bra a a tank ttop. basically she forced cross dressed me i suppose. tennis skirt and tank top while wrists were bound to the ceiling, she then put me in a hogtie i think it's called, ball gagged me and left! she left for a good 30-40 minutes with me helpless and confused. she came back later, blindfolded me and we had a good screw...with the skirt and everything still on. im not really sure what to make of this, we haven't talked about it. i don't understand dressing me up in heels, skirt and tank top. i didn't mind it, it felt nice but why??