Tanya was sitting quietly at lunch eating her sandwich her mother made her when out of the blue her tray was tipped over by Lisa, spilling her milk all over her.Tanya looked up at her tormentor and asked why she did that.

 "You're so fat I thought you could use some more milk!"Lisa said as she took her own carton of milk all over Tanya's head drenching her.

Tanya got up cring and headed for the girls restroom to dry off and collect her thoughts. She had no idea why Lisa always picked on her. It seemed like everyday it was something new. Crying as she opened up the bathroom stall Tanys sat down and balled her eyes out. Seething with sadness and anger she decided it was enough. 

An hour later it was gym time and Tanya knew what she had to do. She made sure no one else was in the locker room when she walked up to Lisa who was changing.

"What do you want porker? Trying to get out of gym, I wouldn't you need all the excercise tubby." Lisa chuckled as she verbally assaulted her rival.

"No I think it's time you learn to treat people nicer."Tanya said

"What are you gonna do sit on me with your fat ass?"

"Well actually yes!" Tanya said as she jumped on Lisa's smaller body and put all her weight on her.

"Get off me you pig,i'll kill you." Lisa said as she began thrashing around under Tanya's weight.

Lisa punched kicked, and clawed but she couldn't budge her larger rival. She began to get tired when she noticed that Tanya seemed to be getting heavier, no not just heavier bigger. Lisa could swear that she was wathing Tanya grow in front of her very eyes.

"Whats going on her, get your fatass off me bitch!"

Tanya could feel the tiny body of Lisa continue to dwindle underneath her. She excerted more and more weight on Lisa until she shrank down further and further. Smiling on the inside as she felt the shrinking process continue Tanya had a good idea of what she was going to do now that Lisa was shrinkin. When she saw Lisa's small body shrink below 1 foot tall she finally let up some pressure not wanting to kill her.

Gasping for breath Lisa looked up at her far more larger and powerful rival. She was too tired to stand up now and looked at the malice in Tanya's eyes. She knew she was in trouble and for the first time in her life knew she needed to plead.

"OK Tanya what is going on here?"she said her voice quivering.

"Well it's quite obvious aint it,I shrunk you. OH stay there one moment I need to get ready for gym."Tanya said as she began stripping down to her panties and bra.

Lisa looked on in awe as she saw the pale chubby girl strip down to her undies. Worse yet was she was still getting smaller and smaller. The evergrowin form of flesh n front of her loomed larger and larger. 

"Please stop this, i'll do anything please!"she whined.

Tanya just looked down at her tormentor shrinking and chuckled. "Nope, you're gonna see what it's like to feel insignificant for once. You made me feel tiny so im gonna make you feel really tiny. Oh and you asked me if I was gonna sit on you earlier and yes is my answer. I just need to take off these panties first."

The now 4 inch Lisa looked on in fear as she saw the massive pale asscheeks of Tanya slip into view. 

"Please don't do this i'll do anything you want."

"I know you will and the first thing I want you to do is kiss my ass!"Tanya boomed.

Lisa tried running but her now 2 inch legs were getting her no where as she saw the large white ass coming down on top of her. Closer closer and closer until the huge white ass came right down on top of her. She expected to feel the crushing weight of Tanya's ass end her life. To her shock she was still alive, but it was completely dark and it smeeled really bad. She hear booming coming all around her as a thunder like voice said"Love it."

Lisa continued to shrink further and further until she was only have an inch tall and at that point the suction of Tanya's ass began pulling her upwards.

"No please not this! I'll do anything anything just please just stop this."Lisa moaned.

Tanya could no longer hear her nemesis and simply stood up and put her panties back on. Her ass cheeks slapped together sealing Lisa and her continously dwindling body in her rectum.

Lisa continued to shrink further and further until she reached 1 mm and got pulled into the inner flesh of Tanya's ass where she would spend the remainder of her days.