The girl he was staring at offers to "help" him with his boner

"Excuse me." Josh was pulled out of his horny reverie by the voice of the busty girl in the tight shirt sitting a short ways away from him. He'd almost forgotten she was there while he was typing, and now he had an even more obvious tent in his pants than he had just from getting caught staring.

"Y-yes?" He asked, preparing for her to chew him out.

"Do you want me to take care of that?" She asked innocently, pointing at his erection. Josh's draw went slack. What the fuck just happened? He thought this girl was going to tear him a new asshole, but apparently she must have been the biggest slut in the world to have been willing to "take care" of his cock before even exchanging names. Unless...

He looked at the phone in his hand again. There was no way it had actually done anything, was there? Then he looked back at her tits. Pushing against the fabric of her top and the deep cleavage poking over the top of it. Either way this was too good of an opportunity to pass up. "Yes." He finally answered.

That was all the encouragement she needed. She stood up and moved from her own seat over to his, scooting over to stand in front of him. With her ass directly in front of his face she undid her pants and lowered them and her underwear both down around her knees. Josh hoped the app had actually worked and that she wasn't just some kind of freak as he lowered his own pants to expose his hard dick.

Then she lowered herself into his lap. He leaned his head back and groaned as he felt her pussy wrapping around his cock and soon she was bouncing up and down, riding him while they both rode the bus. He couldn't keep from reaching around to take two handfuls of her big tits. She didn't seem to mind though. She just kept bouncing. Massaging his shaft with her walls while he mauled her chest. It was incredible.

After a little while he heard her sigh. "There goes my stop." She said. But she hadn't even tried to stop riding him. Apparently she thought taking care of her "responsibility" to help him get off was more important than whatever she was doing. Not that Josh minded.

As he accepted more and more that the app actually did what it advertised he started to feel bolder. He pulled her closer to him and started to alternate playing with her tits and holding her waist to drag her up and down his shaft. When they missed her stop he smacked her on the ass and said, "it's okay. This is worth being a little late for."

"Well yeah. I can't just leave you hard after you popped a boner looking at my tits." She said it like it was no big deal. Like she had just done the obvious, expected thing and there was nothing special about it. That was enough to push Josh over the edge.

After he came inside her she just stood up, every bit as casually as she had sat on his cock in the first place, and pulled her pants and panties back up right over his cum oozing out her pussy. She almost seemed like she didn't notice as she did her pants back up and moved back to her own seat. And Josh smiled thinking about how she'd be walking around now with his jizz in her pants all day.

This was going to be a fun world to live in, he thought as he put his cock away.