just steal some of hers, that's what i did for a while. things like underwear and socks get lost over time, so it's not noticeable. my sister caught me a few times creeping in her drawer but i covered myself by grabbing a pair of socks...that's also before she caught me wearing one of her thongs.
What did she do when she caught you wearing her thongs?
the first time she just gave me a monster wedgie and told me never to wear her undies again or else..of course i didn't listen.
the next time she caught me her friends were over (stupidly i wore white sport shorts with a pink and green thong so she could see it through my shorts) she pulled down my shorts in front of all her friends causing a ton of laughter and then she said "i thought i told you never to wear my panties again!" which led to more laughter from her friends. she threatened to tell mom unless i did what she said. i obliged and took off my shirt as well as my shorts. i was then put on each girls lap and given a spanking, which led shortly to a full on boner. finally, she said that i had to go to victorias secret and try on my own thongs with her and her friends so i could stop wearing hers. they made me try on all kinds of thongs and brought a lot of attention to me. i ended up coming home with two lace thongs and a pair of pink frilly panties.
i never wore the ones that she bought me though, i had an aversion to the whole cross-dressing thing after that experience.
I have to tell you, that sounded like fun being humiliated by a few girls. Did you enjoy the spankings? How many girls were there? Did they make any comments about your boner?
there were only two other girls there, and they did comment on how i had a boner. they remarked about how funny it looked in a thong, and how funny it was that getting spanked was such a turn on. the spankings weren't bad until my sister whipped out a paddle and got me good a few times. i kind of enjoyed getting it from the other girls but from my sister was legitimate punishment.
in retrospect it was kinda fun, but i still get shit about it when they come over (it's been a few years). i get the occasional pantsing to make sure i'm not wearing her panties. one girl usually will pat my butt and make a comment about my boner.