Hermione blushed. "Sorry, Harry. Well, anyways, the main problem is hard for a time traveller to 'aim' themselves properly towards the past. So, I figured, why not just use a second device that helps point them in the right direction? Or time, in this case."
This almost made sense to Harry. But if Hermione understood it that well, he'd trust she knew what she was doing.
"The solution is what my project is! I'm making a temporal beacon. This little device uses runes to emit a signal through space and time, so that when you use it with a paired device, it will always send you back to this particular time."
"This time? So that means that, no matter where... I mean, when you travel from, you always end up back here? I mean, now?"
"Well, yes, at least, the time when we activate the rune set. It's not quite as convenient as the time-turner, but this method lets you travel much, much greater lengths of time. Theoretically, at least. And I'm not too sure, but it might also allow for multiple trips, too, which is another weakness of time turners."
"I see now. But... how on Earth did you manage to get all this done in one year? You were already burning yourself out by taking all the classes! You even dropped Divination because of it!" Harry shook his head at his friend with a look of incredulity.
Hermione fidgeted, looking down nervously. "I may have... bought some extra time with the time turner. More than I needed for the extra classes..."
Harry was curious. Raising an eyebrow, he asked, "How much extra time?"
Hermione mumbled incoherently.
"What was that?"
"...an extra day for every day. Since I dropped divination."
Harry was floored. "Wow! Hermione, I'm shocked! You took out the maximum amount of time from the time turner? Since Easter? Why, you naughty rule-breaker, you!" He started laughing.
"Rule-breaker? Me? You're one to talk! Anyways, I just wanted some extra rest the day I dropped Divination, so I turned it a full day so I could get some extra sleep. But I didn't sleep the whole day, so I ended up spending the rest of it reading and working on my project... and I realized I might be able to get the first stage of it done by the end of the school year if I kept it up."
"So that's why we're down here? The first part of your project is complete? You still haven't explained why you need to be in the Chamber of Secrets."
"I was getting to that! Well, first, I needed a location that could be secret, and wouldn't be disturbed for a long time. It would have to sit undisturbed until my OWLs, when I have to actually hand in the papers for this project. On top of that, this beacon needs a lot of power. I mean, a LOT of power. I couldn't possibly charge it up using my own magic. Hogwarts, however, is built on top of multiple leylines, which are extremely powerful magical veins that cross the Earth. I figured that the Chamber of Secrets, being deep in the ground directly under the castle, would bring me really close to a leyline, and also let me keep this a secret."
Harry finally understood why they were hanging out in the dark, dank chamber with a giant (and surprisingly, not rotten) basilisk corpse. Hermione began to set up her runes, spreading her stack of parchments across the ground, constantly referring to them to place the runes around the chamber while measuring precisely where each should go. It took several hours, and Harry knew they were missing dinner for this, but he was far too fascinated as he watched Hermione work. When she was finally done, she looked up at Harry.
"Harry, there's one more thing I want to ask of you." She was looking straight at Harry, with a very eager and hopeful look in her eyes.
Oh no. Hermione? Is she going to ask what I think she's going to ask? I mean, she is a girl... and the two of us are alone in the chamber together, and nobody else is going to interrupt us. Oh my god, I'm not ready for this... Harry's mind was reeling, as Hermione approached him slowly. Oh no, oh no, she's getting closer. Is she really going to do it? Is she going to ask me to kiss her? I mean, she's definitely a nice girl, and she's my best friend, not counting Ron... wait, no, even counting Ron she's still my best friend, but does that make it better, or worse?
"Um... Harry?" Hermione was right in front of him now, looking worried. She saw him tense up, but she didn't know why.
Harry's brain continued to work in overdrive. Am I too young for this? I'm thirteen... well, almost fourteen in another month or so, and Hermione's fourteen already, and I guess I've heard of people dating when they're fourteen, so I guess that's perfectly normal. But Hermione? She's like a sister to me, isn't she? Could I really kiss her? Heck, could I kiss anyone? I have no idea if I'm a good kisser or not... I can't believe my first kiss is going to be with Hermione. Wait...when did I already agree to this? She's like a sister, right? I have to say no... She's my best friend, after all. Well... suck it up, Mr. Potter. You're a Gryffindor, aren't you? Just give her a kiss. Heck, you almost gave a dementor a kiss a few nights ago, this can't possibly be much harder than that!