Lbdabb/Tina/Tina's room/Quiet/Interrupt/Ass

"Ummmm," Tina continued, unaware of what was about to occur. It didn't matter. Louise had already decided.

"Sorry Tina, but this is for your own good," she said. She popped her thumb into her mouth, letting it linger for a second to make sure it was nice and lubricated. Then, outside where the air felt cold against her saliva-coated finger, she knew that feeling wasn't going to last.

"On the count of three," Louise said, her thumb hovering just above Tina's asshole.

"On the count of three what?!" Tina asked nervously.

"One."

"What's going t-"

"Two."

"Louise wait let me-"

"Three!"

Louise pressed her thumb against Tina's puckered butthole. It tensed and squeezed, resisting with all its might. The hole was small, but the small amount of lube combined with Louise's legendary tenacity, she gave the effort that was needed to get the job done. A moment later, Louise felt her sisters sphincter give way as her thumb popped inside.

"Ahh!" exclaimed Tina, though due to her position her voice was still muffled and inaudible to everyone outside that room, "Louise what did you do!"

"I would have thought that was obvious, Tina," she said. Louise smiled as she moved her thumb ever so slightly, feeling the powerful resistance of Tina's ass. It was nothing like her pussy. This was a place the horny teenager hadn't evidently messed with.

"You're in my butt!" Tina said, her body writhing. Louise didn't have to do much. She barely put anything into it and Tina squirmed beneath her. And all she had in her was a half inch or so of a nine-year-old's thumb.

"Yeah, I am Tina. I told you I needed a good grip." Louise pressed further, stretching her asshole as the widest part of her thumb passed the ring.

"Oww! Louise get it out! How is this supposed to help?!"

"Relax Tina," Louise said, patting one of Tina's cheeks, "no seriously. Relax. You need to stop being so tense. I can't get you out unless I get a better grip."

Tina tried. Louise could feel it. The muscles of her asshole eased up for a moment before tightening again, giving Louise that rubberband-around-the-thumb feeling again.

"Argh! I can't! It hurts so much!" Tina said, defeated, "I'm going to be stuck here forever! I might as well make this dust bunny my new best friend. Hello dust bunny, I'm Tina."

Louise thought about it as Tina asked the inanimate clump how long it lived there. There was a way out of this, she just had to think of it.

• You've gotten this far, no sense in quitting now. Keep trying to get a better grip.
• Try getting Tina to relax by playing with her pussy.
• This was a mistake. Take your thumb out of your sisters asshole and try to get her out more conventionally.