ORER:

You'd to be the older step-sister who farts in the face of your younger step-brother.

You are reading a book or looking at your cell phone when you notice that your younger step-brother is lying behind you, almost with his face buried in your ass.

Then on you say, always in a soft, calm and innocent tone of voice: -That again, little step-brother?

-You what? Are you asking me to fart on your face? I know I did it last time but it was an accident

-Well, to tell the truth I'm a bit gassy today, If you want to stick around, be my guest.