Kill Switch by Penelope Douglas

“So glad I didn’t bring Abby tonight,” Marko said. “I
needed to get off on something new.”
Arion whimpered and moans filled the air around us, and I
saw Winter’s mouth drop open a little like she was about to
run for the hills or break out in a laugh.
“We have to hurry. I don’t want to get caught.”
“Lick me,” Marko told her. “GGet me hard, Ari.”
Winter’s eyes widened, probably realizing it was her sister,
and then I heard a zipper…
“Ah, yeah,” Marko groaned. “Fuck. Swallow that shit,
baby. Nice and deep.”
Winter’s jaw clenched, and she stalked off a few steps and
then broke into a run, back to the house.
I quirked a smile. Well, well, well…
I slipped through an opening in the hedges, pulled up my
hood, and followed her slowly as she headed back up to the
dark, empty house, away from the noise and crowd of the
party.
She scared easily.
Oh, good.