A Centaur

To add to your confusion for the day, Olivia holds out a single costume. From the looks of it, it appears to be the bottom half of a horse.

"Is that it?" You ask, waiting to see her pull out more.

"Yeah, it's a couples costume." She responds, holding it out to confirm what you thought it was.

"Where's the rest of it?" You ask.

"Ugh! You have no imagination." Olivia says with a joking snear. "It's a centaur. You know, half human, half horse."

You want to question it more as Olivia has never been one to show an interest in mythical creatures, but the question quickly fades as you watch Olivia begin to undress.

"It gets pretty warm in there." She says sliding off her top, revealing her perk, rounded, breasts. "Especially if you're the end."

You stare at her now naked body as she moves over to you. She begins unbuttoning your shirt, helping you get undressed as well. You pull down your pants as she takes off your shirt and soon you're as naked as she is.

"Allright! Let's get this thing on." She says.

The only question now is, are you the front half or the back half?