Updated as of 2/14/19
Ron and Harry were both in hospital beds. The girl's had been checked out and their wounds patched up. Hermione sat by Harry but Fiona had left the room some time ago. Harry had just started to wake.
"Harry?" Hermione asked seeing his eyes starting to open.
"I saw my dad," Harry said.
"What...?"
"He sent the dementors away... I saw him. Across the lake..."
"Listen, Harry, they've captured Sirius. Any minute the dementors are going to perform the Kiss."
"You mean they're gonna kill him?" Harry hurried to sit up and grab his glasses.
"No. It's worse," Hermione said. "Much worse. They're going to suck out his soul." The doors to the hospital wing opened and Dumbledore walked in.
"Headmaster, you've got to stop them! They've got the wrong man."
"It's true. Sirius is innocent," Harry said.
"It's Scabbers who did it!" Ron said from another bed.
"Scabbers?" Dumbledore asked.
"He's my rat, sir. He's not really a rat. Well, he was a rat. He was my brother Percy's rat but then they gave him an owl-"
"The point is... we know the truth," Hermione said to Dumbledore cutting Ron off. "Please believe us."
"I do, Miss Granger. But I'm sorry to say, the word of four 13-year-old wizards will convince few others." Dumbledore walked over to Ron. "A child's voice, however honest and true, is meaningless to those who have forgotten how to listen." He patted Ron's foot twice making Ron hold his leg in pain. "Mysterious thing, time. Powerful," he said as he walked back and past the two. "and, when meddled with... dangerous. Sirius Black is in the topmost cell of the Dark Tower." He suddenly turned to face them. "You know the laws, Miss Granger. You must not be seen. And you would do well, I feel, to return before this last chime. If not... well, the consequences are really too ghastly to discuss. If you succeed tonight, more than one innocent life may be spared. Three turns should do it, I think," he said before leaving. He started to close the doors before turning back. "Oh, and by the way. When in doubt, I find retracing my steps to be a wise place to begin. Good luck," he said with a smile before closing the doors.
"What in bloody hell was all that about?" Ron asked.
"Sorry, Ron. But seeing as you can't walk." She pulled out a necklace with a pendant on it. She looped it around Harry's neck as well as her own. Harry went to touch the pendant she was holding but Hermione slapped his hand. She turned something on the pendant three times before it began to spin. Harry watched as all around them everything went backwards and they saw people come and go before stopping when the room was empty again.
"What just happened? Where's Ron?"
"7:30," Hermione said. "Where were we at 7:30?"
"I don't know. Going to Hagrid's?"
"Come on. And we can't be seen," she said taking his hand before running, letting go of his hand in the process.
"Hermione!" They ran down through the clocktower. "Hermione! Hermione, wait!" Harry shouted as they ran across the bridge. "Hermione, will you please tell me what it is we're doing?" he asked. They stopped at the end and Harry's eyes widened. "That's us."
"Hermione, no! He's not worth it," Past Ron said.
"This is not normal," Harry said. Hermione pushed him back and took out the pendant.
"This is a Time-Turner, Harry. McGonagall gave it to me first term. This is how I've been getting to my lessons all year," she explained.
"You mean, we've gone back in time?
"Yes. Dumbledore wanted us to return to this moment." She looked back out at their past selves. "Clearly something happened he wants us to change." Past Hermione punched Draco.
"Good punch."
"Thanks," Hermione said with a smile. "Malfoy's coming." She pushed Harry back and they hid on the other side of a stone wall.
"Not a word to anyone understood!"
"Okay!"
"I'm gonna get that jumped-up mudblood! Mark my words," Past Draco said as he and his lackeys ran by. Harry peeked out in time to see Fiona looked down from watching the three boys run away.
"Come on," Hermione said as their past selves started heading down to Hagrid's.
Harry and Hermione were heading back to the hospital wing, after saving Sirius and Buckbeak – and hiding out of sight until the right time – and had just crossed the bridge to the clock tower courtyard.
"Stop-! It's Fiona," Hermione whispered, pointing to the black haired girl sitting on the edge of the fountain facing them. She hadn't seen them yet so the two moved out of sight. "So this is where she went."
"Let's go around," Harry said. "We can get her to come inside after." He started to move but Hermione grabbed his sleeve.
"Wait, it's… Malfoy?"
"She can handle herself against him," Harry said but in the back of his mind he remembered what he'd seen on the map. Hermione pulled Harry back down with a finger to her lips when he opened his mouth to protest.
"Fiona!" Draco called to the girl as he jogged into the courtyard.
"Since when are they on a first name basis?" Harry asked with a frown.
"I heard you were in the hospital wing; are you alright? What are you doing out here?" Draco asked. "I thought we'd agreed to meet up tonight?"
"Meet up?" Harry whispered. Fiona stood and turned to face him. Draco's eyes widened when he saw the stitched cuts on her cheek and forehead, the state of her clothes and the bandages around her arms. He hurried over to her and put his hands on her upper arms.
"What the hell happened to you?" He put a hand on her uninjured cheek too look at her stitches. Fiona stepped back to get his hands off of her. "Fiona… are you alright?"
"Why should you care?" she asked.
"What are you talking about?" Draco asked with a confused frown.
"You can be so… so insensitive! I know you have to act that way for your precious reputation but you take it too far sometimes! Sometimes I don't know whether it's really you or just an act… It's because of you Buckbeak's dead! You never think about anyone but yourself!"
"Fiona," He let out a big sigh. "that thing hurt you. Excuse me if I wanted to see it punished for that!" he argued with a deep frown.
"He only hurt me after you provoked him! You heard Hagrid tell us hippogriffs are proud and that you should never insult one. And what did you immediately do?!"
"No one told you to get in the way!"
"I didn't want you to get hurt!"
"It's sweet that you care," Draco said with a smirk that only made Fiona frown more.
"Draco..."
"Yes, sweetheart?" Draco asked. Harry's eyes widened.
"Sweet-!" He went to get up.
"Harry, no!" Hermione hissed as she held Harry back.
"Who does he think he is-?!" Harry hissed back as Draco leaned down. Fiona put a hand against his chest to stop him.
"Don't call me that," Fiona said. Draco's smirk faltered.
"Fiona, I-"
"I need to be alone right now. Please. I…" She took a breath. "I can't do this anymore," she said before pulling a ring off her finger, forcing it into his hand, and then slipping passed him and quickly walking away, into the clock tower.
"Fiona! Wait-!" Draco called after her but she rounded a corner and was gone. He stared down at the ring in his hand then kicked the fountain before sitting down and slamming the side of his fist against it. "Damn it…" he muttered before putting his head in his hands.
"Come on," Hermione said with a frown. She pulled Harry, who looked ready to kill Draco, along.
The two returned to the hallway of the hospital wing as Dumbledore was closing the doors. They ran up behind him as he turned around.
"Well?" he asked them.
"He's free. We did it."
"Did what?" he asked as he walked around them. "Good night," he said with a smile and a little wave before walking away. Harry and Hermione looked at each other before going into the hospital. They saw themselves across the room right before they disappeared. They walked in and Ron pointed at them.
"How did you get there?" Ron asked. "I was talking to you there. And now you're there."
"What's he talking about Harry?" Hermione asked as she glanced mischievously to Harry
"I don't know," Harry said. "Honestly, Ron. How can somebody be in two places at once?" Hermione grinned and laughed quietly. They heard footsteps behind them and turned to see Fiona walk in.
"You're awake," she said giving Harry a smile but he could see underlining sadness in her eyes.
"Are you okay?" he asked.
"I'm fine," she said. "Just a few scratches."
…
On the train ride home the four Gryffindors sat in a compartment, Hermione explained to the boys how she'd taken so many classes that year. She had decided to drop Muggle Studies so she'd have a normal schedule again for the next year. Ron brought up that the World Quidditch Cup was that summer and offered for Harry to stay at his place and he could go with his family; his father normally could get tickets from work. He extended the offer to Fiona and Hermione who accepted. The four got through a few games of Exploding Snap before the witch with the tea cart arrived and the four enjoyed a large lunch.
It was late in the afternoon when Hermione noticed something outside the window. Harry turned to see what it was and recognized a tiny owl holding a letter that looked too big for it. He hurried to open the window, seeing as the owl was struggling to keep up with the train, and reached out to catch it. Once inside the owl dropped the letter onto Harry's seat before it began zooming around the compartment. Grimm and Crookshanks, who were sitting beside their respective girls, looked up to watch. Ron saw Crookshanks watching and snatched the owl safely out of harm's way. Harry picked up the letter and grinned seeing his name.
"Who's it from?" Fiona asked.
"Sirius!" he exclaimed before reading the letter aloud to them. Sirius and Buckbeak were in hiding but he'd planned on letting a few muggles see him so the security on the school would be lifted. He confirmed that the one to send Harry the Firebolt had been him and that Crookshanks had been the one to help him, getting the portrait passwords, trying to get 'Scabbers' and sending out the order for the broom.
"See! I told you it was from him!" Hermione said with a triumphant smile.
"Yeah, but he hadn't jinxed it, had he?" Ron pointed out. "Ouch!" He looked down at the little owl, hooting happily, that had nibbled his finger in what it seemed to think was an affectionate way.
"He's sorry about scaring us in the beginning of the year," Harry said as he looked to Fiona.
"That was him? And he wasn't trying to scare us? Could've fooled me," she muttered with a playful smile. Harry read some more and his eyes lit up as he saw a note giving Harry permission to go to Hogsmeade.
"That'll be good enough for Dumbledore," Harry said happily. And it turned out the owl was for Ron since Sirius had cost him one rat.
"Keep him?" Ron asked. He looked at the owl closely before holding it out to Crookshanks to let the cat sniff him. "What do'you reckon?" he asked the cat. "Definitely an owl?" The ginger cat purred. "Good enough for me!"
Harry held the letter the entire rest of the ride, reading and rereading it. He held it as they crossed through the barrier at King's Cross station and they saw his uncle standing a few feet from the Weasley's. Mrs. Weasley hugged Harry and Uncle Vernon sneered realizing what they were.
"Where's your dad?" Harry asked, not seeing Fiona's father.
"Oh, I forgot, mum sent me a letter yesterday saying dad had to work late the past few weeks and mum wouldn't let him come to get me. She figured I could just… catch a ride home with you?"
"Of course, if you're sure you want to ride with him." He glanced towards his uncle who looked rather uncomfortable seeing the large family of red headed wizards.
"I mean I also get to ride with you," she pointed out.
"I'll call about the World Cup!" Ron yelled after them as they waved goodbye at him and Hermione. They wheeled their trolleys over to Vernon.
"What's that?" he snarled at the letter Harry was still holding. "If it's another thing for me to sign you've got another-"
"It's not," Harry said with a smile. "It's a letter from my godfather."
"Godfather?! You haven't got a godfather!"
"Yes, I have," Harry said a-matter-a-factly. "He was my mum and dad's best friend. He's a convicted murderer, but he's broken out of wizard prison and he's on the run. He likes to keep in touch with me, though… keep up with my news…check if I'm happy." Harry grinned at the look of horror on his uncle's face and Fiona nodded in agreement. "Oh, by the way, Fiona needs a ride home." Fiona smiled up at the man before the two started to push their trolleys towards the exit.
A/N: So, as I was working on this one I realized that the scene in the hospital wing takes place the same night (I don't know why I thought it was the next morning) and in the movie Harry, Hermione and Sirius land Buckbeak in the courtyard where I wrote Fiona and Draco having their argument/break up. SO… yeah, my bad on that but I didn't want to remove the scene or move it, cause no other place would make sense for Harry to also see and then be forced to not immediately confront her.
There's multiple reasons it doesn't work where it is and I tried to explain away some of them like why was Draco up so late and looking for her = he was waiting for her to show up at their meeting place and she never showed. (He presumably over heard someone say she was in the hospital.) How she can be there when the Harry and Hermione are supposed to be there at the same time = they were there but ended up hiding out of sight because it wasn't the right time to return to the hospital wing yet.