A Full Day Blowjob

You smile, turn to your sister, and say. "Hey sis, I'm going to need your help to cum today." Your sister's face quickly falls into a sour expression. "Fine, but I have a modeling job soon, can you make it quick?" Andrea responded.

"Nope sorry sis. You see I need to cum in your mouth and I think it is going to take you several hours if not all day long, you should call in and say that you can't come in today because you are going to be helping your brother cum."

"That shouldn't be an issue, you know that your not going to last more then 5 minutes in my mouth anyhow." She smirks.

"You think so? Well I will need you to be topless in the living room in 5 minutes blowing me, to help me cum."

--- 5 minutes later ---

You are lying back against the corner of the couch, without a stitch of clothing on on, when Andrea with about 6 seconds to spare, she is covering her breasts with her left hand, and it doesn't appear that she is planning on letting you see them as she blows you. She walks directly up to you, kneels down and starts giving you one of the best blowjob you have received to date.

"Andrea, you made it just in time." You reach down to fondle the exposed portion of, and get your hand slapped by her free hand.

"What the fuck do you think you are doing?!" she exclaims on a small pause of blowing you.

"Andrea! Language!" you hear your mother shout from the dining room table.

"[sigh] Andrea, let me say this just once, because I do not want to have to tell you each and every step. If I look, leer, grope, or do anything to you, when my dick is in you, it is to be considered needed to help me cum." you say with an exasperation, and a roll of your eyes. "Move your hand so I can use your tits, as I see fit."

You reach down and start to give her tits a good mauling, "One last thing, and this is special for just today, but to be able to cum, I need to you to keep your mouth fully sealed around my cock until I give you permission to remove it."

As you have been reexplaining the rules to your sister, she has been continuing to a wonderful job with her mouth, and you know you will not last much longer. "Andrea... 'oh god!' when I start to cum. 'ahh fuck your mouth is so good' ...when i start to cum, have only the head of my cock in your mouth, I need to know that you will get to taste my cum. 'yes!' Here I cum!"

As you relax back into the couch, letting go of your sisters tits that have had very rough squeeze applied to them, basking in your post orgasmic high. "Wow sis, your right I don't think I lasted more then 5 minutes in your mouth." She is just sitting with your cock still in her mouth glaring at you. "I would let you get up sis, but you see. I need to cum, and I need your help to do so. I'll need you to start off by swallowing that load I just left in your mouth, and follow that up with a extremely slow blowjob, I'm talking you completing one full bob of your head taking a good 8 to 10 seconds."

Your mother walks into the living room, "Kids, I'm going to go to the grocery store, do you need anything before I go?" as she looks down at your sister, "Andrea I'm so proud of you for taking care of your brother's needs. I was very worried that you wouldn't help him out."

"You know what yeah, two things, can you bring me a large water bottle, I want to make sure I drink a whole bunch of water today, and as Andrea can't unseal her mouth from around my cock for the full day, moving to grab it myself would be kind of difficult. Oh and a pen and pad of paper for Andrea so she can communicate."

"Sure no problem honey." Your mother walks back into the kitchen, and on her return she is holding a one of the large 64 oz soda cups that you saved from the local gas station last time you got a soda, a small notebook, and a pen. "You to have fun, and no fighting when I'm gone" She leans in and gives you a kiss on the forehead, and kisses your sister on the back of her head. "I'll be back in an hour or so."