Tim and Tina were sister and brother. They were both millennials in their twenties living with their parents in a creaky old house on the edge of town. Tim and Tina's parents went away one summer on a long holiday in Spain, leaving the two siblings alone in the house. This was Tina's last year in the family home. After summer was over she planned to move out and go to college. Tim had already graduated from high school and had no plans for his life. They were both adults and it was a bitter sweet time because they were going to go their own ways and they were going to miss each other. Tina and Tim loved each other very much and they knew they would miss each other sorely. This was their last summer together, and with Mom and Dad out of the house, they had great fun playing and reliving the games of their childhood.
On the first day of summer vacation, Tim sat alone in the living room reading one of his sister's plentiful fashion magazines. Well, to be clear, he was not literally reading it. He was thumbing through it, looking for scantily clad models. If he was lucky, he might find a topless one. He didn't see any of those, but he stopped at a photo spread of a skinny young model wearing a tiny bikini. Tim contemplated the pictures carefully, and his hand absently found its way to his shorts where he began to caress his growing interest.
His sister Tina walked silently into the room. She wasn't wearing shoes and her stockinged feet barely made a sound. She stopped abruptly and stared, not sure if she was really seeing her brother stroke his cock through his shorts while he perused a magazine. She stifled a laugh and watched as he took it even further wrapping the cloth of his shorts around the shaft and he stroked its length hungrily.
Tina tried to hold it in but a snicker forced its way through her lips with a blurble.
Tim turned to his sister, suddenly aware of her presence, with a look of horror. His hand still held his cock, but froze in mid stroke.
Tina could not contain her amusement as a wide smile brightened her face. "Watcha doing Little Brother?" she asked innocently.
He stammered in response and quickly yanked his hand away from his manly erection.
"Oh, I see," she said with mock realization, "you're looking at the spring swimwear. You know it's only girls' swimwear, though. There's nothing in there for boys. I didn't know you were so interested in girls' fashion. That might be useful, though." Tina put her finger to her chin, thoughtfully, while entirely ignoring her brother's hardon. "You know, I wonder . . ."
Tina smiled even wider as she looked at her brother's stupefied face, his mouth hanging open.
When no response came, she continued, "Can I show you the swimwear I bought the other day? I would absolutely love to have your opinion. Would you mind? It will only take a few minutes."
"Um," was the only response, but by that time, Tina was already on her way to her bedroom, with a cheerful lilt to her walk.
On her return to the living room, she was wearing a mauve one-piece with a gathered neck and high cut legs. She catwalked to her brother, where he was slouched on the sofa. She put her hands on her hips, cocked her head, and slowly pivoted around until her back was to him. She looked at him over her shoulder, "The back is the best part, don't you think?" She gyrated her hips to emphasize her ample and half-naked ass, the high cut hips left most of her ass cheeks out in the open.
She held the pose, but no sound came out of her brother's mouth. He pulled at his shorts, trying to straighten them out, but it was obvious that he was still hard and bulging.
"Hey," she blurted, "you know what would be fun? You could take pictures of me! Let's do it! Take my picture, like I'm a model."
"You want me to take your picture?" he said doubtfully.
"Yeah, lots of pictures. It will be fun. I'll be all dumb and sexy like a model and you can leer at me and take lots of pics, like a real photographer."
Slowly, Tim's hesitance ebbed, and his excitement began to take over. He agreed after only token resistance. He pulled his phone out and his face looked eager, much to his sister's delight.
She faced her brother and took a variety of poses as he took photo after photo. "What do you want next, Mister Photographer?" she said in her best Marilyn Monroe. "Do you want to see my back side? You're the photographer. All you have to do is tell me what you want and I'll do it."
As he assented, she turned her half-naked bottom to her brother again and gyrated one way then the other, looking over her shoulder coyly as he took more photos. Soon Tim's hard on was bulging and throbbing.
"Is that precum?" Tina asked with a smirk.
Tim looked down, and saw what she was looking at. A small spot of wetness had appeared on his shorts at the very tip of his tent pole.
"Oh, that's perfect. Don't move. Wait til you see my bikini. Your going to love it."
