Zoe (c).

"Hey Jimmy!" Your glistening, naked half-sister stands before you, completely unfazed by the intrusion. She smirks as she looks you up and down, and you yelp as you frantically back out of the shower.
"Jesus, Zoe! I thought you were Jenna!"
"Yeah I figured..." she chuckles, still even toned. "You didn't see my acid washed shorts and pink tank on the floor there?" You now notice the clothes on the floor that clearly don't belong to your wife.
"Don't freak out, you big baby. It's not a big deal. You can even come in and share if you want." You pull your boxers back on and pull your shorts up.
"Naw, I think I'll pass." Just the memory of her body is giving you....bad thoughts.
{if Zoe2Plan = 1
} "Worried you're going break your restriction, edge boy?" her chuckle fills you with humiliation and arousal.
"No...." you hate how small your voice is. {else
} "Oh come on, Jimmy. Don't be such a prude. It's just a shower."
{endif
} "I'll just wait my turn." A thought occurs. "By the way... where is your car?"
"Oh it broke a tie rod, so I had to get it towed to the shop. I took an Uber back."
"Do you need....?"
"No, Jimmy. I can take care of myself!" the anger in her voice is nothing new. Zoe would never hesitate to ask for a place to crash, or a ride, or turn down a free meal, but she would rather die than accept money for something like a car repair.
"Fair enough. So you'll be on your way then?" You keep your voice light.
"Dick." she's caught in her hypocrisy, but she's not going to change. "Well if your not going to wash my back, get out. You're leeching my steam."

You head downstairs, shaking your head as you pull on a t-shirt. The front door opens to admit Jenna and Karen. You greet them, though they are busy gabbing about the days activities.
"Who's in our shower?" Jenna asks once she hears the water.
"Zoe."
"Oh? Her car's not here." she looks puzzled.
"Something wrong with it, she had it towed to the shop."
"Oh...that sucks. Just not her week, huh?" Jenna looks concerned. "The girls aren't home yet either, huh?"
As she says the words, Riley pulls into the driveway. She walks in with some grocery bags: it looks like she and Allison are having tacos for dinner tonight.
The rest of the afternoon passes without incident. Jack comes home around 3:00, and heads up to take a nap before dinner. You made reservations at Chat Noir this morning, setting them for 6:45 PM, so at 5:30, you shave, get dressed in a nice pair of slacks, and a deep blue shortsleeve button up shirt. Jenna brushes out her hair and puts on makeup, wearing sheer knee high stockings under a tight dress, with a garter thong and no bra as far as you can tell. Your mouth waters as you watch her dress, and she winks at you as she clasps her nylons.

You head downstairs where Jack and Karen are waiting. The smell of tacos lingers in the air, and the girls are eating by the poolside. Zoe's with them. Karen's wearing almost the exact same outfit as Jenna, though she's clearly wearing a bustier under her dress.
"You guys ready?"
"Abso-fucking-lutely, Jameson!" Karen pronounces with gusto. Jack looks a little sleepy. Probably still whipped from his encounter today.
Jenna comes down, and the four of you head out, taking an Uber so that you don't have to worry about driving home.