Mess with her mind.

After two hours in his room Mark decided to see what his sister was up to. Walking downstairs he found her sitting on the couch watching some shit on MTV. He didn't know what it was and he didn't particularly care.

Sitting down on the recliner he immediately stopped time and walked over to his sister. Pulling open the front of her leggings he saw that she had replaced her stolen blue thong with a pair of pink cotton panties. "Tsk tsk, sister. You know you're not allowed to wear panties in this household" he mockingly admonished her. Pulling her leggings and panties off in one fell tug he pocketed the pink undies. Reaching forward Mark pulled her tight lips aside and gave her clit a few rubs before jamming a finger up her cunt. He rubbed it around a bit, not being particularly gentle and then removed it. He pulled her leggings back and up and made sure to give her another camel toe. Sitting back down in the recliner he watched her from the corner of his eyes as he started time again.

She gave a quiet little yelp and her hand shot to her crotch. She then realized something felt off. Sneakily she pulled open the front of her leggings to find her panties were gone. "What the fuck...again?" she whispered to herself.

"You alright, Ashley?" Mark asked with fake concern.

"Oh yeah...I'm fine" she replied.

After 10 more minutes of watching TV Mark had his most genius idea yet! Standing up he said, "Hey I'm gonna go get something to drink, you want anything?"

"No thanks," Ashley said back.

To get to the kitchen he would have to walk right past her. And as he was mid-stride in front of her he stopped time. Quickly undressing and stowing his clothes away he got back in front of his sister. He quickly jerked off his cock until his 8 inches was rock hard. He got back in position of mid-stride and quickly started time and half a second later he stopped it again. He let himself go soft, then dressed, resumed position and started time again. He continued walking to the kitchen where he grabbed a soda from the fridge. Walking back to the living room he saw that his sister had a confused look on her face. From her perspective it looked like she seen her younger brother naked, with his long hard cock for a split second. He hoped that his actions had the desired effect of making his sister think that she had subconsciously imagined it. He may have to do it a few more times just to really drive that thought home for her.