Pinch her nipples

Haley took her left hand away from Alex's wrist and grabbed her right tit. Alex wasn't wearing a bra and the soft flesh beneath her shirt squished in Haley's grasp. Haley could see the shocked expression on her sister's face. She could have gotten her phone back, but Alex's breast felt too good and Haley wasn't close to being finished. She pressed harder into Alex's breast. She was feeling for her nipple until she felt it harden in her palm.
"St-stop it Haley," pleaded Alex.
"Awe, why?" Mocked Haley knowing she just gained the upper hand. "Doesn't it feel good?"
"N-no," said Alex trying to pull away.
"Awe, come on. Your nipple is already hard. I know you like it," said Haley as she squeezed harder. "I bet all the guys want to get a handful of these puppies."
"R-really?" Asked Alex who stopped resisting her sister.
"Well, I don't know about all the guys, but, and I hate admitting this," said Haley as she momentarily stopped squeezing and just rested her hand on her sister's chest. "But Dylan has had several dreams about titfucking you."
"Titfucking? What's that?" Askex Alex trying to sit up, but Haley pressed her back onto the floor.
"Come on, even you can't be that lame," Haley laughed. "It's when a guy puts her dick between a girl's tits and squeezes them around it. And then fucks them."
"Oh my God, and you like that?" Asked Alex.
"I can't really do it," said Haley looking down at her chest. "Not big enough, but yours would be perfect. Hell, I'd fuck them."
"Eww, stop being gross," said Alex as she tried to pushed Haley's hand off of her, but Haley didn't move. In fact, Haley just realized how damp her pussy had gotten just from feeling up Alex.
"Come on, here's your phone back," said Alex holding the phone out to Haley. Haley ignored it. She was too focused on how pretty her sister was and how sexy she had become since her chest filled out. Haley had been with girl's before, but Alex was different. They were sisters, although, neither of them were going to get pregnant if they did fool around. Haley desperately wanted to fool around. She was very horny and thought Alex was the same way. She was breathing heavy and stopped trying to push her off of her. Alex was staring at her.
"I don't want the phone," said Haley leaning towards her sister and squeezing her nipple between her thumb and index finger. Alex took a quick breath from the sudden shock of having her nipple pinched. Haley knew it felt good. Haley put her other hand behind Alex's head and pulled their lips together for their first true kiss.
Alex stiffened under her touch, but reciprocated the kiss as best as she could. Haley slid her tongue into Alex's mouth slowly testing the water. Alex stiffened again at the intrusion and tried to pull away. Haley could sense her hesitation, but kept going. She swirled her tongue around Alex's.