Part 1
The violet alicorn paused, adjusted a beaker, and then circled the library once more. She needed two more ingredients for her experiment that it seemed she lacked. I really thought I had that. She thought. And that. She added, looking under more books.
“Spiike!!” She called out, only to turn around and see the little dragon standing behind her. Before he could say anything, she gave more orders.
“Oh good, Spike, can you please help me find those pegasus feathers I’ve been saving, I need them for an experiment,”
“Experiment?” He said wearily. 
“Twilight, it’s Hearts and Hooves day!”
“I know it is, and in the spirit of today, I’m doing an experiment!” She gave a hearty gesture, almost sarcastic.
“Oh and can you cook something please? I’m absolutely dying of hunger,” Twilight said, walking past him.
“Uh, but what about the feath-“ He said, but was interrupted. “Ah yes, I’ll just go out for more now,” Obediently, Spike headed out of the room, wondering how she was going to get pegasus feathers. Wondering if she was actually going to ask or just pluck them from some poor ponies back.
Twilight in a flurry of excitement, flung open the door to see a familiar blue pegasus standing there, bewildered.
“Rainbow Dash, Just who I need!” She yanked the mare inside by the shoulder, who tried to resist.
“Uh, Twilight..” Rainbow said, fluttering her wings nervously and backing up from Twilight. “What are you doing?” Before Twilight answered, she took hold of some of Rainbows blue feathers with her magic, and plucked them off.
“Ah!”
“An experiment,” She said a bit softer, seeing her friend’s pain.
“Uh, yeah, of course,” Rainbow said sarcastically. Twilight paused from her excited state, and stood face to face with Rainbow Dash.
“Right. Why did you come here anyway?” Rainbow started sweating nervously as Twilights wide purple eyes stared straight at her. She fiddled with the small piece of paper on her back and tucked safely under her wings.
“Uh,” She fumbled simply.
“Right,” Twilight said, smiling. “Mind helping me with an experiment?” Rainbow quickly removed the note from her back as Twilight turned away and slipped it somewhere safe.
“Sure,” Rainbow followed Twilight across the library.
“Really? You want to do… this? With me?” Twilight sounded honestly surprised.
“Of course!” Rainbow dash said, of course, lying. She wasn’t really interested in doing an experiment, but she did actually want to spend some time with Twilight. 
Rainbow had been thinking to herself a lot about what she would do on Hearts and Hooves day. She didn’t feel it was even time to express her feelings for the precious nerdy alicorn, but a certain yellow pegasus had pushed her to do so.
“Since you’re not going to ask…” Twilight gathered Rainbow’s attention again. “My experiment is to see the change in effect after the change of magical ingredients added in a mixture of correct ingredients in certain magical potions!” Twilight didn’t have much time to prepare that and shamed herself for making the explanation so unscientific. But even so, Rainbow had trouble understanding what she meant.
“How about a translation from egghead speak,” Rainbow mumbled. Spike, done with his task, suddenly entered the room to help her.
“She’s trying to brew a potion different times with different ingredients each time,” Rainbow took a moment to understand Spike’s words, but nodded.
“I think I get it,” Rainbow thought about it further. “What potion are you testing?” Twilight smiled to see Rainbow actually asking more about it.
“Well, in the spirit of Hearts and Hooves, I’m using a love potion,” Eyes growing wide, Rainbow stepped a little closer.
“How are going to test the effects?” Rainbow secretly scoffed at herself for talking like such an egghead, but she wanted to know more.
“Well,” She pondered for a moment. “I haven’t figured that out yet, for right now, I’m working on simpler differences like the appearance of the potion,” Twilight chimed happily.
“Okay… So why did you pluck me?” Rainbow asked.
“That’s one of the ingredients, a pegasus feather”
“I see,” There was silence for a moment as it seemed Twilight was trying to remember something.
“RIGHT, now, I have to get the final ingredient for my test, would you like to… Come with me?” Twilight tilted her head back, looking at Rainbow.
“Sure,” She said cooly.
Out on the street, Rainbow watched as Twilight stealthily slid along the sides of the streets, scouting out her ingredient.
“Uh, Twilight, what is it you need?”
“A pegasus feather,” Twilight whispered. Rainbow looked at her blankly.
“I thought you already got that from me..”
“No! It has to be from a filly,” Twilight ditched her hushed tone and stood up; a few ponies looked over at them.
“And why are you sneaking around?” Rainbow said, holding back a small burst of laughter.
“Well. I need to get a feather, so…” She said, realizing her actions were a bit silly.
“Here, let me,” Rainbow pushed out her wing in front of Twilight in gesture to stop her from doing anything more. With a small flutter of her wings, she flew over to three certain little fillies. Twilight watched as Rainbow got her the feathers she needed and returned with them in less than a minute. Her eyes sparkled in gratitude.
“Heh, thanks…”
“Yeah, I don’t think that was that hard,” She laughed. For a moment they just stared at each other before Twilight flew off towards her library. Rainbow hesitated a moment, locked in a haze. She felt a calmness rush over her as she thought about how this day had been going. She looked up to see Twilight was waiting for her in the sky, and she shook out of her daze to join her. They realized they had gone farther than they expected as they flew across town towards Twilight’s library. Twilight paused a moment in the sky, putting a hoof on Rainbow’s shoulder, stopping her as well.
“Twilight?” Rainbow said, confused.
“Rainbow, really, why did you come by today? And today of all days, shouldn’t you be out with, you know, you’re special somepony? You told us you had one,” Rainbow gulped nervously, wondering what to say as a response. Not wanting to say nothing, she pulled up an excuse.
“Well, we’re not together, and I heard you’d be alone to so I thought we could hang out,”
“But Rainbow, I’m not the only one alone today, what about Fluttershy? Or pinkie pie?”
“I already went to see Fluttershy today, and I didn’t get much from hanging out with her, and I’m pretty sure Pinkie Pie is busy,” Rainbow Dash was lying both times, but she knew Twilight probably wouldn’t know. As she guessed, Twilight believed it, and they kept flying. Only for a short while though since they had reached their destination. They entered through the window and landed softly on the wooden floor. Twilight sighed.
There was a silence in the room that Rainbow had not expected; Twilight bowed her head.
“You know, doing all this experimenting on Hearts and Hooves day isn’t really what I wanted to do,” Twilight suddenly stated in a lower tone. Rainbow wanted so much to ask what she did want to do, but she stayed quiet, hoping Twilight would say so for herself.
“You know? I just thought I’d have a special somepony by now,” Twilight said, sitting down on the lowest step. Please don’t start talking about love. Rainbow thought to herself.
“I’ve thought about how Flash-“ Twilight began, but as soon as the orange pegasus’ name came up, Rainbow Dash flew up in a flurry of angst and anger. Twilight looked up, utterly confused and bewildered.
“I just remembered. I have a thing.” She said, enraged, as she flew out of the library right over Twilights head.