Almost getting caught

We were pretty wrapped up in what we were doing when I heard the squeak of the second to last stair coming up to my room. I liked to call that my secret warning stair. I quickly yanked the blanket over Isabella and I and pulled her hand off of my dick. Just in time too because my sister Jenna came into view at almost that exact moment.

"Hey guys, what's going on?" she asked looking at us apparently none the wiser as to what was going on under the blanket.

"Oh nothing, just the usual hanging. Why?"

"Well, you guys didn't come down for lunch and I was wondering what was going on up here."

"Is it past lunch already? Crap. Well, I guess we can sneak down for food in a couple minutes." I said. That was when I felt a cool hand snake its way down to grasp my dick again. That crazy girl was going to get us in so much trouble if she wasn't careful. Be careful not to show my surprise, I continued, "Sorry if we worried you. Isabella fell asleep and I didn't want to wake her up."

"No problem. Just making sure you two were okay and not getting yourselves into trouble." Jenna responded with a wink.

I resisted the urge to sit up to give her crap but I did say, "Wait a sec, I'm older. It isn't your job to make sure I'm not getting into trouble. That's my job for you. So why don't you head back downstairs and leave us alone."