I knock on the door hesitantly as the muffled sound of my sister crying suddenly halts. After some shuffling, the door opens to reveal my big sister wiping her eyes and putting on a strained smile, "Oh, hey. Did you just get back from work?" she asks clearly putting on a cheery front.
"What's wrong? I thought I heard crying..." I reply confused.
"Oh...uh, I'm fine," she says before clearing her throat. "I was just uh... okay, I'm not fine. I did something stupid and now I'm scared," she confesses now not crying but still sniffy.
"Can I come in and we talk about it?" I ask stepping into her room and closing the door behind me.
"You can thanks, but uh... I want to show you something but you must promise you won't freak out." She continues while she sits down on her bed.
"I promise," I say while sitting next to her.
She looks at me hesitantly but sighs and to my surprise begins pulling off her jeans and panties.
"W-woah sis what are yo-" my sister unveils an erect cock with an almost menacing throb that makes me blush and swallow nervously.
"This is my cock..." she looks at her hard and pulsating meat with sadness and frustration, "I was born a Futa, but Mom still wanted me to be her 'perfect little girl' so I've never been allowed to do anything with it. I had to learn mental exercises in order to stop it from getting hard and I spent most of my teenage years in a chastity cage. I've never done anything with it but clean it." she explains sadly.
"But earlier today, my curiosity got the better of me. So I snuck into Mom and Dad's room and I kinda stole one of Dad's viagra pills... then I took it." tears well up in her eyes as she continues, "And now it's really hard and I don't know what to do! It's been like this for over two hours now and it hurts! I've never been fully hard before! I'm scared!" she cries and buries her head in her hands.
I gently put an arm around her and pull her into a hug as I think of a solution to her problem. I feel the heat emanating from her cock and smell the musky scent of her arousal, I oddly enough found myself salivating, "Sis, I can help you with your problem," I offered encouragingly.
"Really?" she asks looking at me through puffy eyes.
"I uh... I could help teach you how to use your cock," I offer with a smile.
She looks up at me with hope in her eyes. "You'll what? Teach me?" With a smile, she pulls me into a tighter hug.
"Oh thank you thank you thank you!" she cries happily before kissing me on the cheek. "You're the best little brother a big sis could ask for! So uh, what do we need to do to make it go away?"
"Well, normally we would need to make you... cum," I explain nervously.
She looks at me then at her cock curiously, "How do I do that? I mean, I know how to do it with my pussy. But I'm completely clueless when it comes to cocks."
You blush and look at her sheepishly, "Well you would usually start by rubbing it." You point to her dick which is currently standing straight up, though starting to droop slightly due to its own weight.
"Oh, so I just rub it?" she asks excitedly.
"Yes, until you cum," you answer simply.
"Okay... could you maybe uhm... show me? Just so I know what to do, then I can try it myself." she offers hopefully.
You nod nervously and kneel between her legs as she looks down at you with anticipation.