Go see what your family is up to

As you leave your room, you think about taking a shower, but you can hear your older sister humming her favourite shower tunes. You unconsciously wish she wouldn't take so long, and then you hear the shower turn off. Instead of the usual half hour post-shower routine, the door opens after ten seconds and you are faced with your sister, wrapped in a towel and still dripping wet.

Jill is one year older than you, and your mind calls back to the few occasions you've seen her this revealed. You also remember a couple impassioned masturbation episodes as a result of this. You realize that your new powers could give you some fun here.