He goes to have a look

Curiosity got the better of him. He needed to see what she was doing. Needed to see if she looked any different while performing a normal task. Mason set the laptop aside and stood up. His legs felt stiff after sitting so long. He walked quietly toward the kitchen, not sure what he expected to find.

Serena stood at the counter with her back to him. Her long black hair was pulled into a loose ponytail. She was chopping vegetables with steady, precise movements, carrots and an onion from the bottom drawer of the fridge. The knife moved up and down in a regular rhythm. From this angle he could see the side of her heavy breast pressing against the thin t-shirt fabric every time she leaned forward to cut. The outline of her nipple was visible through the material.

She hadn’t noticed him yet. Or if she had, she didn’t react. She just kept working, completely focused on the task like it was the most important thing in the world. Mason leaned against the doorway and watched for a minute. This was the closest thing to normal he had seen since he walked in on her earlier. If he ignored the blank look in her eyes when she turned, it almost felt like old times when she used to cook for him during visits.

But it wasn’t normal. Not even close. She was only doing this because he told her to. Because her programming made her thank him for letting her be useful. The contrast hit him hard, the caring big sister who used to make him grilled cheese at midnight, versus this version that would probably bend over the counter and let him fuck her if he said the word.

His cock stirred again at the thought. He hated it. After that long fantasy earlier he had promised himself he wouldn’t let it happen, but the images kept sneaking back in. Her ass up on the counter, shorts pulled down, moaning “you’re the best!! Mason!” while he railed her. He tried pushing the thought away but failed as he found himself clearing his throat.

“S-Serena??”

His older sister stopped her chopping as she perked up and turned to face him. “Yes Master! How may I be of service?” She said obediently, knife still in her hand, body facing him fully.

Mason’s mouth felt dry. His heart was beating fast. He knew he shouldn’t, but the words came out anyway in a shaky unsure voice.

“Can you take off your top for me?”

Serena’s eyes went wide with what seemed like excitement. She nodded furiously, hands already reaching for the bottom of the t-shirt. “Yes Master, right away Master!” She said as she effortlessly pulled it over her head in one smooth motion. Her massive tits fell free and came back into view, heavy and full, bouncing as they settled. The dark nipples were already stiff, pointing straight at him. They looked even bigger without the shirt covering them, soft and round with that perfect weight that made them sway slightly with her breathing.

Mason found himself staring almost enchanted by them. He couldn’t look away. The way they hung there on her chest, the smooth olive skin, the slight curve underneath where they met her ribs. He had imagined this exact sight so many times but seeing it up close in his own kitchen made his brain short-circuit.

“Master? What is your command?” Serena asked submissively, breaking his titty trance. She stood there topless, the knife still held loosely in one hand, waiting patiently.

“Um… nothing. Just continue what you were doing,” Mason said meekly. His voice came out weaker than he wanted. This felt wrong but he had already seen her naked so there was no point in making her cover up now, was there? He was just testing limits anyway, he justified to himself. There was nothing wrong with just looking, was there? It wasn’t like he was touching her. He was still in control.

Serena just nodded as she returned to her chopping. She turned back toward the counter and continued slicing the vegetables. Her massive tits hung down and bounced with every motion of the knife. Each chop made them sway heavily, jiggling in a way that kept drawing his eyes. Mason could see the way they moved independently, soft flesh rippling every time her arm came down. He found himself enamored as he walked into the kitchen unconsciously, moving closer and closer until he was only a foot away from her.

Serena, to her credit, just continued prepping the meal as he had asked her to. She didn’t comment on how close he was standing. She didn’t try to cover her chest. She simply kept working, hips shifting slightly as she reached for the next carrot. Mason was so close now he could smell his sister’s sweat. All this work was surely working up a sweat. He had always known his sister’s unique smell, her natural scent mixed with whatever lotion she used. She was a physically affectionate person after all, never shying away from hugs even when they got older. She would pull him into her chest and hold him tight whenever he had a bad day. But now that he had such intimate access to her, her smell triggered all the primal parts of his brain. It was warm, slightly salty, feminine. It made his cock throb harder in his shorts.