As the next day proceeded, Alexandra still couldn't stop thinking about the previous night. To try to wipe her smile away was a pointless exercise, no matter how hard she tried.

      Mike had obviously noticed the slight change in her behavior and her good mood, so he kept questioning her about it all day, to which Alexandra would only shrug and try to change the subject each time.

     That afternoon once their classes were finally over for the day, Mike bid Alexandra goodbye as he went down to the Quidditch pitch with his team to practice for the upcoming game, which was in a few days.

      So with that, Alexandra went up to the library to try to finish up her Transfigurations essay as she took her usual seat by the window. Although she ended up placing her head on the table, staring at the world outside the window, trying to enjoy the view of the large mountains and the marvelous lake while the sun was setting over the horizon.

      But just then, her head snapped up and she was dragged back to reality when someone behind her said,

      "Hey."

     Turning around and glancing behind her shoulder, Alexandra felt a spark rush down her spine when she spotted Regulus standing there with a few books in his hands.

      "Is that seat taken?" he asked with a smile, gesturing at the chair next to Alexandra.

     "No." She shook her head, her heart fluttering as Regulus placed the books on the table and drew out the chair, taking the seat next to her. "What are you doing here?"

      "I promised that I would help you with Potions, didn't I?" He grinned.

     Alexandra giggled. "Yes, but I didn't think you were serious."

      "Why not?" Regulus shrugged with a smirk, opening up one of the books. "So which part is the hardest for you?"

      "Er... all of it?" She smiled nervously.

      Regulus laughed. "Better get started, then."

Regulus started off by explaining the basics and the easy Potions that they were sure would show up in the upcoming O.W.Ls. But an hour had barely that Alexandra started yawning uncontrollably, growing tired of studying again.

Every once in a while she would glance behind the window and watch the sun set, only to be replaced by the infinite stars and the mesmerizing moon.

"Alex!" Regulus said sharply, snapping her out of her thoughts.

"Yes?" Alexandra gave him an innocent smile.

"Are you even listening?" He raised a brow at her.

      "No."

     "Okay, that was... blunt." Regulus chuckled. "Look, I know you're not really fond of Potions, but you gotta get through your examinations."

      "I know, I know." She sighed. "I'm sorry, I just can't focus on something for too long. My mind eventually wanders off."

      "Oh, yeah?" Regulus grinned. "And where has it wandered off to this time?"

      "To the Black Lake," said Alexandra in a quiet tone so the librarian wouldn't tell them off. So she looked back behind the window, smiling. "The water's so still. But underneath it... there's a whole other world."

       Regulus glanced at her admirably as Alexandra had her head turned away from him. Sometimes she talked so passionately about something that surprised him.

      "There are so many things living under there," she went on, "Grindylows, Giant Squids, Hippocampus, and even —"

      Alexandra stopped in mid-sentence, her smile widening as she turned to face Regulus again, the excitement glimmering in her eyes now.

       "What?" Regulus asked hesitantly, knowing from the look on her face that an idea had just popped into her head.

      "I've got an idea!" she said enthusiastically, hardly able to hide her excitement.

      But before Regulus could ask what she was on about, Alexandra quickly started packing her stuff and putting her books and quills in her bag.

     "Quick, let's go!" she exclaimed, urging him on.

      Regulus was so confused at what was going on, but he did as he was told and so he packed his stuff as quick as humanly possible, running out of the library after Alexandra in a hurry.

      "Could you at least tell me where we are going!?" Regulus yelled after her, but Alexandra didn't slow down.

      "You'll see!" she shouted back as she kept running with Regulus right after her until they reached the grounds and made their way over the Black Lake.

      "Alex...?" Regulus said unsurely as he watched her place her backpack down on the grass as she walked closer the Lake, where numerous little boats were floating at the edge; the same boats that the first years took.

      But then his eyes widened even more when Alexandra got into one of the boats.

       "Come on, then!" she said cheerfully, gesturing him over. "What are you waiting for?"

      Regulus hesitated at first. He looked behind his shoulder at the castle. He was pretty sure getting on these boats weren't allowed, specifically at this hour of day, now that it was dark.

      But with one last sigh, he put his bag down and made his way over Alexandra's boat, cautiously trying to get on it. At last, he finally managed to sit down next to her with difficulty.

       "Are you ready?" Alexandra asked, her smile wider than ever.

      "Not really." Regulus gulped worriedly.

      But Alexandra had already taken out her wand and tapped it on the boat. On cue, the boat started moving forward, floating gently upon the still water. Regulus clutched the sides of the boat, not sure what to expect.

      They floated in silence along the water for long minutes in silence. Regulus was staring worriedly at Alexandra, meanwhile her eyes were dreamily watching the waters, as if she could see the depths of it.

       But to his horror, after long minutes Alexandra took out her wand once they were in the middle of the Lake and tapped it again on the boat, causing it to come to a stop.

      "We're here," she said quietly, looking down at the water.

      "Alex?" Regulus started, gulping nervously. "Not that — not that I can't swim, or anything — but I really hate water and whatever creature lives underneath it."

       "This is gonna change your mind," she whispered. "Trust me."

       Alexandra then looked up at him and gave him a gentle smile, and with that, Regulus somehow felt more at ease. Her smiles always had that power on people.

       But what caught Regulus more off guard was when Alexandra took a deep breath, closed her eyes, and then started singing.

      Her voice rolled over the hills in sorrowful waves. The words left her lips so smoothly, so softly, that Regulus felt like he was suddenly enchanted by it as he listened.

      Alexandra's voice echoed through the lake, and as Regulus watched her sing with her eyes closed, he felt a strange warmth in his heart and felt as if her voice had touched a part of his soul that he didn't know even existed.

      But then, he let out a gasp when he thought he saw something move in the water right behind him. Regulus looked over his shoulder in fear, his heartbeat speeding up. He heard it again, causing his heart to sink.

      "Alex?" he whispered urgently, looking around him at the water in horror. "Something's moving."

       But Alexandra didn't stop singing. She kept going. Now Regulus was sure that he wasn't being paranoid, because he saw something pass the boat.

      A long fish tail.

       Just then, Regulus let out a loud yelp when he saw a head slowly surfacing from the water, only a few feet away from their boat. But he went even paler and all color drained from his face when he saw more of them; dozens of what he thought for a second were ugly human surfaced, surrounding their boat.

       Although, when he breathed heavily a few times to try and calm himself down, he realized something. Alexandra wasn't the only one who was singing.

      Around a dozen mermaids were nearing them through the water, all singing. He could hear a magical music from the depths of the water, as if the lake was singing along. The mermaids' voices were so mesmerizing that Regulus stopped frozen on his spot, watching with his mouth hanging open, enchanted by the music.

       Alexandra had stopped singing and opened her eyes, watching the mermaids around them with a smile as they kept singing and the magical music kept playing, so beautiful, so breathtaking, as if it was cleansing their soul and warming their hearts. The mermaids weren't exactly saying words known to them, but the melody was enough for them to lose themselves in the moment.

      The magical music filled the air without effort, like the waves filling holes in beach sand; the sound rushing in and around them as they sat on the boat. They watched the mermaids whose faces were lightened by the shining moon above, which had its reflection upon the water like glimmering diamonds.

       "Beautiful, isn't it?" Alexandra whispered over the sound of the unforgettable music, looking around her dreamily, as if she belonged to a whole other world.

       But just then, right at that moment which was filled with music and magic, Regulus felt for a split second like he belonged to her world.

      So he looked at her sideways, and without her noticing, he let a genuine and warm smile form on his lips while he glanced at her.

      "Yeah," Regulus whispered as he smiled, his grey eyes fixed upon her. "So beautiful."