A/N: Phinbella. Spoilers for "Act Your Age."

C is for College (Phineas Flynn Always Keeps A Promise)

Every Friday like clockwork, Phineas and Isabella would meet up at the campus café no matter how many extra credit assignments he hadn't finished or how much student government tried to monopolize her free time.

"One large double-shot in the dark for me, and one medium caramel chai breve with agave syrup and extra whip for the lovely lady, please." Isabella said he didn't have to loudly proclaim her beauty every time he ordered coffee for her, but the blush on her face betrayed her. Besides, he'd spent way too long not saying corny things like that to her.

Phineas was eternally thankful that Isabella's patience, and not just because she'd waited over 10 years for him to return her feelings. It seemed just as miraculous that she'd put up with him for over a semester of study dates that would almost always devolve into the same thing by hour's end: Phineas talking about memories he made with his step-brother.

"One time Ferb..."

"Then Ferb was like…"

"Haha, that reminds me of when Ferb…"

It'd taken him longer than it probably should have to notice the glazed look in Isabella's eyes by ten minutes into him rambling about something he and Ferb had done as kids (which, more often than not, she'd also been around for anyway.) Once he noticed, he tried to tone in down, but more often than not time taken away from discussing Ferb was spent apologizing for going on the tangent in the first place rather than talking something Isabella was more interested in.

And that was just on their dates. He'd lost count of the number of times he'd asked Isabella to help him with a project and had called for his brother when he needed a wrench. In retrospect, he had never really thought about how the person he spent his entire childhood bouncing ideas off of every day was going to be in another country for at least four years. Compared to huddling together around a blueprint, each holding one end of a steel beam, and tossing a box of nails across the lawn, video calls left a lot to be desired.

It wasn't until he was walking her home on a dark winter evening that he realized just how badly he'd messed up.

"Hey, are you really okay with things the way they are?" Isabella asked, tightening her shaky grip on his hand.

It was one thing for Phineas to make Isabella annoyed; that happened fairy often, and she would always explain in great detail exactly what he'd done to ruffle her feathers. It was a whole other thing for him to make Isabella worry. "Wait, what?"

"It's just… you two are a team. You always used to do everything together. I…" She stared at her feet, "It's not like I wouldn't want to be your girlfriend if we didn't go to the same school. You could have gone to the same school as Ferb, right? I mean…"

"…Waitwaitwait." He flailed his free hand in the air and tried to process what Isabella was saying. "…Have… you been blaming yourself for Ferb and I going to different schools?"

"Well, if the acceptance letter fi-"

"Hey, c'mere." Phineas took Isabella's other hand and took a step closer to her. "Ferb wanted to spend some time in the country he was born in, and I wanted to stay close to home. But even if I'd been thinking of going to school on another planet, it was my choice to go to college with you. This is what I want to do."

"Yeah, but-"

"But nothing." He smiled warmly. "Leave worrying about the Atlantic Ocean to me, okay? No matter what, I'm not going to lose either of my two favorite people. I promise." He didn't let Isabella protest before kissing her under the starry sky.

Sure, he'd recently started to realize he had the emotional empathy of a slab of concrete, and needed to work on his habit of talking like the other person wouldn't have more than one sentence to respond with, but both he and Isabella were well aware he always kept a promise.