You need an ally for what's to come...

Despite your past irritation with Gwen's antics, she's still your sister and has always been there for you when you've been in trouble. You desperately do not want to be alone right now, and the urge to rush downstairs and reach out to her is hugely strong.

You manage to contain yourself, as you know that confronting your sister with a complete stranger's body would be counter-productive to say the least. Instead, you reach again for your phone.

Hey sis, you ok? I guess u r about home frm work? x

There is a muffled beeping from downstairs. You sigh at the juvenile deception that you're **** to resort to, but the last thing you want is for Gwen to burst in before you've laid the groundwork.

True to form, she responds almost immediately.

Gwen: HAHA spooky, I jst got in. Wots up? xo

John: I gotta bit of a prob I need ur help with. It's gonna sound weird.

Gwen: WTF lil bro wot have got stuck up ur ass this time?

You smile despite yourself. When you were a kid you'd managed to get some stupid toy stuck up your bum and had begged Gwen to help rather than face up to your parents. It had been a sore point for over a decade and she never let you forget it.

John: LOL nothin quite like that. Even weirder. ... Um ok I'm just gonna spit it out. I'm at home. Some1 is gonna come downstairs. You have to believe that it is me... ok?

Gwen: ??? u r freaking me out now John. Wot is going on?

So there you go. No turning back now. You throw on a hoodie and some track pants and tentatively pad downstairs. Gwen is waiting for you in the hall. A look of absolute confusion crosses her face as she realises the person coming down the stairs in her brother's clothes is a sexy young woman...