If the elves want my underwear then they have to do the following -
1: Take me out on a real date - one where they pay, not me, and take me someplace nice. (You know, I've never been on a real date.)
2: Seduce me with chivalry - open doors for me, treat me in a slightly old fashion manner, but agknowledge women are equal to men.
3: Show that they're not ashamed to be seen with a fat woman in public via Public Displays of Affection (PDAs) - not total groping but giving me a kiss, holding my hand, offering me their arm, etc.
4: Take me back to their home after softening me up and seduce me. The tickle me silly.
Then I shall get undressed, including underwear, so they can tie me up and tickle me and the rest.
Oh, but elves, FYI, I'm allergic to latex, so you need a different type of condom. And spermicidal lube.
But at the end of the night, I shall put my undies back on and go home.
That's the only way they're getting me to take them off for them.