Kink bingo: exposure/exhibitionism

Five times Phineas unintentionally saw more of Isabella than he ever had before, and the first time he saw all of her on purpose.

M-rated for nudity (some underage/teen), language, and sexual content.

Partly inspired by Nudity Buffer by Erica_T (on AO3).

Explanation for non-American readers: first/second base are a reference to a baseball-themed teenage way of "keeping score" for the physical part of a relationship. First base is kissing; second base varies regionally, but in this case is 'groping above the waist'.

Phineas was twelve the first time he saw Isabella's panties.

It was another day full of adventure and invention, helping Isabella and the Fireside Girls gain another patch. This time, it was a skydiving patch, and Phineas was providing support from below while Ferb flew the plane they'd built for the girls to jump out of. Phineas's radio crackled, and Ferb said, "Isabella's going...now."

He watched her falling through the air, his heart in his throat for no reason he could identify. Why am I more worried for Isabella than I was for, say, Ginger? Whatever the reason, he felt relief wash over him when her chute deployed. He looked up, watching her descend, and suddenly realized he was looking straight up her skirt. He wasn't sure why the girls were jumping in their Fireside Girl uniforms, but he blushed at the sight of her pink panties. And then the wind shifted, and the view was gone.

As she landed, he ran over to her and took her hand. Knowing she was safely down comforted him in some way he couldn't name, and the bright smile she gave him made him feel all warm inside.

Phineas was almost fifteen the first time he saw Isabella's bra.

"She's upstairs, Phineas. Just go up," Vivian said.

Phineas ran up the stairs, banging through Isabella's partly-open bedroom door and accidentally crashing into her. She was changing shirts, and he'd caught her wearing just a lacy white bra.

"Phineas!" she shouted, jumping back and covering her chest with her just-removed shirt.

"Sorry!" he said, running back through the door and pulling it closed behind him. "I'm sorry, I didn't realize..." he apologized through the closed door.

"I didn't think I'd need to worry about privacy in my own bedroom," she said testily.

"The door was open, and I didn't think. I'm really sorry." He'd been noticing recently that Isabella was turning into a woman, and a stunningly-beautiful one at that. He had definitely found the way she filled out that bra to be very interesting. "I hope you aren't too mad at me."

"No, I could tell it was an accident. Besides, usually a boy tries for first base before he tries for second," she said.

Phineas spluttered, "I wasn't trying for second base..." and heard Isabella laughing as her clothing rustled.

That sounded almost like an invitation, though, he thought. Should I?

Carpe diem. "Does that mean I should try for first?" he asked.

The door opened and Isabella walked out wearing a snug pink T-shirt, denim shorts, and an impish smile. "Maybe," she said.

He leaned over and gave her a quick kiss on the lips.

Or, at least, he'd meant it to be quick. Isabella seemed to have other ideas, and the kiss rapidly deepened as she pulled him closer.

Phineas was barely fifteen the first time he saw Isabella topless.

It was a beastly-hot day in Danville, with temperatures climbing into the triple digits, so Phineas and Ferb had decided to build a water park. Phineas's girlfriend Isabella had helped build it before dashing back across the street to change into her bikini. They'd been dating just over a month, ever since their first kiss slightly before his fifteenth birthday.

They'd toured the water park together, and were riding the huge high-speed slide that was the centerpiece of the park. Phineas had gone down the slide first, and was waiting at the bottom when he saw it happen, as if in slow motion. Isabella was holding her arms up triumphantly as she went down the slide - and then, her bikini top whipped up her arms and off of her, leaving her topless.

The image of Isabella's bare breasts - round and soft and peaked with dark-brown tips - burned itself into his brain in the few seconds before she recovered and covered herself with her arms. He grabbed a towel and waited for her at the bottom of the slide, wrapping it around her as she stood up. She gave him a grateful smile and went off to find her errant top.

From behind him, Buford clapped him on the shoulder and said, "You, my friend, are a lucky, lucky man."

Phineas was sixteen the first time he saw Isabella's bare ass.

"Dare," Isabella said boldly.

With an evil grin, Gretchen said, "I dare you to moon Phineas."

Everyone else's eyes went wide at this. Isabella's eyes narrowed, then she nodded at Gretchen. "Fine. But you specified Phineas, so everyone else needs to turn around."

Phineas was stunned. They'd been dating a year, and he hadn't gotten to see Isabella topless again since that brief moment the previous summer; now she was going to flash her ass at him?

"How will we know you actually did it?" Gretchen asked.

Isabella smiled. "You'll know."

With just a little grumbling, the rest of the group turned around and faced away. Isabella walked to the center of the circle, unzipped her shorts, turned away from Phineas, and pulled them down.

Phineas's jaw dropped. She was showing him - and only him! - those two perfect orbs, pale on one half of her tan line and darker on the other. He'd gotten a hand on them a few times during particularly passionate makeout sessions, but only through two layers of clothing.

And then, her dare complete, Isabella pulled her shorts back up and zipped them again. "Okay, folks, you can turn around again."

"So did she, Phineas?" Gretchen asked, then laughed when she saw the look on his face. "I'll take that as a yes."

Phineas was seventeen the first time he saw through Isabella's clothes.

Phineas and Ferb were crouched over the incomplete engine of Ferb's kit AC Cobra, looking for Candace's engagement ring. Candace had come over to watch them build Ferb's new car, and her ring had fallen off her hand and into the engine block...somewhere. She desperately wanted them to find it before Jeremy came over in a few hours; he'd just given her the ring three days before, and she didn't want him to think she didn't appreciate it.

Ferb was using the X-ray goggles they'd built that morning to peer into the engine block, trying to find the ring. He shook his head and handed the goggles to Phineas, who put them on and tried to trace the path the ring might have taken as it fell into the open cylinder head.

"What'cha doin?" Isabella said, walking into the garage. Phineas looked up and over at his girlfriend...and then froze.

The goggles let him see through her clothes. He could see all of her, as if she were wearing nothing at all. He'd seen her topless before - they'd gotten to a point where second base was a frequent destination for the two of them - and he'd run his hands over her curves through her clothes many times, but he'd never seen her fully naked before.

Quickly, he turned away and tore the goggles off. "Oh my God, Isabella, I'm sorry..."

Isabella looked at him, puzzled.

"We're working with X-ray goggles to look for Candace's ring, and..." he said, trailing off.

Ferb laughed and said, "I'll let you two sort this out," as he left the garage.

Isabella cocked her hips and said, "So did you like what you saw?"

Phineas felt too embarrassed to speak, and merely nodded his head.

She came up to him and gave him a quick kiss, then said in a low voice, "Once we get married, you get to see that every day. Or at least every night."

Maybe I need to talk to Jeremy about advice on proposing, he thought.

Phineas was nineteen the first time he saw Isabella naked intentionally.

Isabella - his wife Isabella, and he'd been waiting for that day forever - had gone into the bathroom to get ready for their first night together. With a mischievous grin, she'd told him not to even bother with pajamas tonight, and he sat naked under the covers of the bed in their honeymoon suite. After four years of dating, and many years of teasing each other before that, the teasing was finally over - they were husband and wife, and they'd both been eagerly awaiting this night.

He wondered what she was going to wear to bed tonight. He knew her friends had taken her to a lingerie store during her bachelorette party, and she'd said she couldn't wait to see his reaction to the outfits they'd bought for her. He briefly thought about what she'd look like in shimmering satin or translucent lace.

The bathroom door opened; Isabella came out, and Phineas's breath caught. There was no satin or lace; there was just Isabella, completely bare before him.

"You like what you see?" she asked with a seductive smile.

He nodded, and said, "I do. Very, very much." Firm breasts topped with chocolate-brown nipples, stiff from arousal; the glorious curve of her hips, just aching for a hand to stroke across it; the carefully-trimmed thatch of hair between her legs, pointing downwards to unexplored territories. She spun slowly, and he saw the soft slopes of her back and the tight shape of her ass, and then she came over and joined him in the bed, sliding the covers down so she could see all of him as well.

"I know you were looking forward to seeing what the girls got for me," she said seriously, "but for tonight, I didn't want anything between us at all. I'll dress up for you some other night."

Phineas nodded as she lay back in bed, pulling him with her. He stroked his hand back along her cheek, then ran his fingers through her long black hair; he continued down along her side, resting his hand on her bare hip, reveling in the warmth of her skin against his own. "No rush," he said. "We've got the rest of our lives to explore each other."

In a breathy voice, Isabella said, "Let's start exploring."