Sexy Fun Times/Wank/Hang/Shower/Leading

"You know, little girls who tease their big brothers, sometimes get more than they bargained for," you say.

"Can I see it," she asks with a grin.

"If you really want to; but you've got to promise you won't tell anyone."

She holds up her fingers in a salute; "Girl Guides honour." Hesitantly, you open your robe and she gets her first proper look at your stiff cock. "Wow!" She says. "I never knew they got that big."

You wrap your hand around your shaft and start sliding the skin up and down; she watches with her mouth open, mesmerised like a rabbit in the headlights. After a minute, she tentatively reaches out and you let go to give her free access. She's not the first young girl to wrap her small hand around your cock, but Katie's your sister and you keep getting that memory of her as a baby kicking her chubby little legs in the air as you slid your preteen cock back and forth along her slit.

You take her hand in yours and demonstrate how to slide the skin up and down. "You squeeze on the upstroke and then just slide it down again," you say, and she does as she's told.

"Will that make the sperms come out," she asks.

"It might if you do it right," you say. You sit and enjoy her clumsy attention for a while. "You know what you saw that girl doing in the film," you say.

Katie nods, looks up at you, and then down at your stiff cock. "It's too big," she says.

You shake your head. "I've seen you sucking ice lollies bigger than that," you say. She opens her mouth experimentally and then leans over; you can feel her breath on the swollen head of your cock and you sit still until she plucks up the courage to take it into her mouth. You wince as her teeth scrape, but you don't say anything because the head of your cock is in her hot wet mouth and you can feel her tongue licking the end, probably tasting the salty pre-cum. Your balls are tight and the temptation to fill her mouth with spunk is great, but you hold back, wanting more.

Eventually, she lifts her head and you feel the cold air on your wet knob-end. "Did I do it right," she says, breathing hard through her mouth.

"Yes sis; that was brilliant."

"Then why didn't you squirt yet?"

"Sometimes it takes a while; maybe if you took more of it into your mouth and held the shaft at the same time… I'll tell you what though."

"What?"

"Maybe if you took your top off and showed me those new boobs you were telling me about."

Her budding tits are just small mounds with a tiny pink nipple on the top. She sits up, pushes her chest out and cups her hands underneath to make them look bigger. "They're beautiful," you say, and you really mean it.

"I thought boys only like girls with big boobs," she says.

"Some boys do, but for me, yours are absolutely perfect."

She smiles and lowers her head again. This time there is no scrape and her lips are soon clamped around your shaft. The temptation to push her head down is almost irresistible, but you know that would scare her and you want this to be the beginning of an ongoing relationship. She pulled still for a few moments, breathing through her nose and then her head goes down further until you feel your cock at the back of her throat. She gags, but only a little and holds it there for ages before pulling up and letting it go once more.

"How's that," she says, triumphantly.

"Amazing," you say, and you mean it. "Another few seconds and I would have been pumping all those millions of sperms straight down your throat." She giggles and looks down at your cock again, all shiny with her spit and your pre-cum.

• Get her to swallow it
• Finish off by hand so she can see you squirt