Raid Megan's room

Hyper aware of the cool air on your very naked, still-unfamiliar body and the effect its having on your nipples, you waste no time going straight into Megan's room in search of clothing. You've spent virtually zero time in your sister's room in recent years, and you certainly never expected to be going through her underwear drawer looking for something to wear. It's all you can do to remind yourself that it's not all that weird, you're a girl now, for some reason, and you need underwear. Everything is fine.

You get lucky when the very first drawer you pull open does, in fact, contain her underwear. I guess it's good we're about the same size... Women's underwear is so different from men's. It's soft, almost silky. Luxurious, even. Sometimes a bit of lace or other decoration, and the sheer number of styles is crazy! You choose quickly, largely by random feel. Something with a particularly nice feel that also isn't a thong. You pull it out and step into it, enjoying the softness as it glides up your smooth thighs and nestles snug against your sex.

Megan is surprisingly organized, so it doesn't take long to find a perfectly matched white bra. It feels good to be a little bit less naked. You take a moment to appreciate the sight of yourself in Megan's full length mirror. You look impossibly cute in your tiny white underwear. You even start turning yourself about to examine your reflection from various angles, and tugging on your panties playfully, imagine what sort of sexy selfie you could produce.

When it occurs to you that you would totally masturbate to the sight in front of you, you freeze, realizing you're looking at yourself. Wait, no, that's not your real self. Right? This is getting confusing.

You quickly search through her other drawers for something you can wear, eager to just get dressed and get out of there to avoid any further confusing interactions with your sister.