Erika tried to look as nonchalant as possible, though every move would remind her of her swollen nipples inside her shirt. Fortunately, they weren't tenting through her hoodie at the moment.
"Hey mom!" she let out with a bit of a husky voice, just as Emily squirmed on her chair; the erect canine member trapped in the bottle dragged it against the underside of the table with a slight scrapping sound. Erika's eyes widened, looking straight accross the room, and Emily froze, stopping the friction.
"So, does your mom knows you're here?" Erika's mother asked Emily.
"N-no, I need to call her I-I think..." she struggled to articulate. Slowly, she put her hands under the table and grabbed the bottle, pushing hard. She felt a light pain as it forced her erection down, but it also throbbed in anticipation as it stimulated it further. She gulped audibly.
"Do you want me to call her for you maybe?" Erika's mother went on while tidying the countertop of the kitchen.
Emily discretly pulled her dress over the bottle and kept her hands over it, pressing it against her thighs. She didn't understand why it felt so painful and pleasant at the same time.
"Y-yes please, I'd like that", she almost whimpered with a blush on her face. She felt the balls between her legs pulling closer while her knot rubbed inside the bottle. The goo she leaked sloshed around, smearing the inside of the bottle even more.
"Okay then", Erika's mom replied, and she left the kitchen. Erika immediately turned to Emily and tried to pull on the bottle.
"Quick! We don't have much time..." she whispered to Emily, yanking on the bottle without a warning. But the bottle was still stuck, Emily's knot keeping it in place. The petite girl let out a lewd yelp and covered her mouth with her hands. She could hear Erika's mom on the phone in the next room.
"Yes, Emily's here... Alright..."
Erika gave another hard tug on the bottle and Emily stiffled a moan. She felt an orgasm coming. A burst of cum splashed inside the bottle, followed by several more.
"Erika!" Emily whimpered in pleasure and pain, as her friend kept jerking the bottle around. After a minute of rough handling, the knot slipped out with a wet pop. Some cum splattered on the floor and Erika triumphantly brandished the bottle above the table, before putting the cap back on.
"Hide this in your bag, quick!" Erika whispered as the girls looked around. Emily grabbed her schoolbag at the feet of her chair, shoving the bottle inside just as Erika's mother was walking back in. The wet member was still leaking goo down her chair and she buried its flesh between her thighs and squeezed hard, hoping it would soften soon enough.
"Your mom is coming over as we speak", Erika's mother announced in the kitchen while Emily and Erika were straightening themselves on their chairs. "Everything's alright here?" Emily's face was red and almost sweaty.
"Yeah mom, thank you!" She felt the colder ambiant air brushing against her lowest teat set, which were poking from under her hoodie. She discreetly tugged on the hem to cover them before her mom could notice.
"You two could work on your homeworks until Emily's mom gets here", Erika's mom suggested. The two friends were too embarrassed to argue, though they struggled to concentrate on their exercices. Emily kept thinking about the bottle in her bag; she couldn't wait to drink the goo to turn back into a girl, even temporarily, but she couldn't do it in front of Erika's mom, who was still around in preparation for dinner.
Finally Emily's mom showed up and Emily slowly got up, picking up her bag awkwardly. The thing between her legs swung under her dress at a downward angle but remained hidden. Erika watched from the window as her friend climbed into the car and left. Her breasts were hurting again, and she feared she would explode milk in front of her mom.
"Mom, I'm going to shower!"
"Sure, I'll call you when dinner is ready, pumpkin".
Once locked in the bathroom, Erika removed her clothes and stood for a minute in front of the mirror...