Lisa sat on the bed while Eric finished up his changes.
She watched him stand and turn, he said "OK all done things should start happening... now!."
Lisa saw nothing for a moment then she noticed that Eric's pecs looked a little larger, then she realised his nipples had gotten bigger too. She was staring at his chest and suddenly she realised what was happening, he was growing breasts!
She started to say something, then stopped entranced, as his breasts grew from modest to large, well above her B's, then suddenly a bra formed on his chest and his nipples were no longer visible. She looked up at him, confused, he grinned at her.
"Not done yet!", he said. "The next part will start in a moment."
As he was talking she noticed that she was finding his new chest distracting, she also noticed his grin get wider when she found herself looking at his chest again.
"I see you like the view, but my eyes are up here!" He said with a stifled laugh.
She gave him a look. "I'm not used to liking boobs that way, they're distracting!"
"I know, but it was such a perfect opportunity to say it. I couldn't pass it up."
"I guess you're right it is kind of funny."
"Oh, here comes the next part" said Eric, as he glanced behind himself at the screen.
Lisa found herself admiring the shape of Eric's breasts from the side as he twisted to look at the screen. She was even distracted enough that it took her a moment to notice the strange sensations coming from between her legs.
This time the change had happened much faster, and by the time Lisa noticed it was happening it was over. She shifted uncomfortably felling between her legs with her hands and looking down, she realised what had happened, she now had a dick, and with how much she had been looking at her boyfriend's chest she had a hard on. Even though her clothes had adjusted to be cut with room a hard on in jeans wasn't the most comfortable introduction to having a dick.
She notice Eric was looking at her crotch.
"I have the opposite change between my legs, and I swapped our sexual preferences for between the legs stuff too."
"Swapped?" Lisa asked.
"Yeah, that's my dick you've got there."
She looked down again and then back up at Eric.
"Basically since you would normally enjoy the view of me tenting out my pants, the way you are right now, I now like that view, and if I say tell you that the nice tent you pitched is making me wet you'll find that makes you..." Eric said, trailing off and letting Lisa fill in the rest.
He was right, the idea of him having a pussy and it getting wet WAS turning her on more.
"Wow this feels weird." Lisa said, "I mean not just the physical changes but liking boobs and the other changes... but it's also kinda neat"
"Yeah, I'm looking forward to finding out what it's like for you when you're on top. Also it's not just preferences related to genitals that swapped, it's a lot of stuff related to how we respond to sexual stimulation too. Like if you moan intellectually normally, I will now. Basically we get the essentials of the other's experience."
Lisa felt her hard-on intensify. "Except your boobs are huge, very nice though, but now I'm really interested in getting you into bed." She stood up and wrapped her arms around Eric at his waist and shoved her hands down the back of his pants so she could grab his butt and kissed him. She then shifted her stance to make sure he could feel her erection against his leg since that had been something that always turned her on.