Disclaimer: Don't own and never will.

AN: Written for round 8 of the Quidditch League. (Round 7 was our BYE round, where we didn't have a game.) This time it's the Eras tour playlist and for myself, the prompt is

"I don't wanna keep secrets just to keep you." Cruel Summer

AN2: Trigger warnings for an abusive/manipulative relationship between two characters with a questionable age gap. And none explicit mentions of underage sexual activity.

Demelza Robins quietly seethed as she watched Marcus Flint flirt with a blonde Hufflepuff girl.

She knew WHY he was doing it. She knew what he was like when they had started their relationship and the rules they had set down. Well, he had set down really. He was the one who knew what he was doing after all. He was the older, more experienced half of their relationship. He was the one who knew what a relationship was like. Not the silly romance novels like those favoured by her older sister, but the real deal. He loved her. She knew that. The scene before her was just a part of his cover for their relationship. She knew that. It was part of their cover. A means of hiding a relationship that others would call inappropriate. (But what did they know? Just because she was thirteen and he was nineteen. There was a bigger age gap between her parents than a mere five years and nobody considered THEIR relationship inappropriate.)

It didn't help.

Marcus looked up at her and gave her a small, subtle smile. The smile he normally gave her that made her go weak at the knees. The smile that said that she was special and loved and that his flirting was just a cover, that she was the only girl who mattered. She was the only girl who was in his heart and his bed.

"Hey Demelza, what's up?"

Demelza sighed. She had been staring again. Staring and putting their relationship at risk. Marcus would have been disappointed by her lack of maturity here. It was one of their rules. Don't stare too long. Don't let other people see anything that would raise questions. Don't leave any hints about their feelings towards one another. Nobody could ever know the truth. At least, not yet.

Her friend Gemma looked at her with concern. Demelza's feelings were clearly showing too much

"Sorry... I was just...lost in thought," she said and Gemma raised an eyebrow. Demelza inwardly sighed. Her best friend knew her far too well. Or Demelza was being more obvious than she thought. (She really hoped that it was the former and not the latter.)

Gemma grinned, her blue eyes lighting up as though she had realised something.

"You have a crush on him, don't you?" she asked with a smirk and a slightly teasing voice. Demelza inwardly sighed with relief. A crush would at least be more acceptable. Nobody would think that it was anything more than that. They certainly wouldn't think that it was anything else. The hidden dates, the quiet looks, the hidden kisses and the more intimate times that made her uncomfortable, but she did because it was what he wanted from her.

She looked at Marcus one last time, ready to turn away and continue on her way to dinner. The blonde Hufflepuff was walking away with a smile on her face and Marcus smirked, before giving Demelza a quick look. Or rather, THAT look. The one that said they had to talk and talk now.

She made an excuse to her friend and slipped into a nearby classroom. Marcus was waiting for her with a dark look on his face. A pit formed in her stomach. He was angry, she could tell. Angry and disappointed? She wasn't sure.

"What the fuck do you think you're doing?" Marcus demanded angrily and Demelza winced. "You know the rules. You're not supposed to stare like that. You know that nobody can know about us. Not yet."

"When?" Demelza asked and he looked at her in shock. She didn't blame him. She hadn't even expected to say that, let alone anyone else.

"What do you mean when?" he asked angrily and she recoiled slightly as if he had struck her. (He never had of course. He loved her. That's what she told herself. He was just angry about her stupid mistake out there.)

"Errr..." She flailed as she tried to explain and Marcus's scowl deepened.

"Well what the fuck is it? I'm not fucking psychic you know!"

"When are you going to acknowledge me as your girlfriend?" she asked. Marcus opened his mouth to speak, but Demelza continued, suddenly unable to stop. Her words flowed rapidly, coming faster and faster, like the breaking of a dam inside, unleashing a torrent of words that she hadn't even realised she was holding back.

"Why are you always flirting with other girls, but I can't? Why do you always push my boundaries, but I can't set any? Why do I have to fold to your wants and needs, but you only listen to mine when you want? Why do you even flirt with other girls in front of me when you know how much it hurts me?" At this point tears were running down her cheeks, but she didn't care. All her emotions were flooding out and she didn't care about his answers.

"Come on darling..." he started, reaching his hand towards her and a look of love on his face. Or at least what she had thought was a loving look. Somehow she wasn't so sure about that now. She pressed on.

"You know Gemma just thought that I had a crush on you? A one sided attraction like a celebrity crush. Not a secret relationship between us. Not a boy I've been dating since my thirteenth birthday four months ago. Not the person I had my first kiss with. Not the boy I lost my virginity to, even though I wasn't really ready, but I loved you enough to let you push me into it! And despite all that, you're angry because I didn't like seeing you flirt with another girl!"

"Are you fucking serious Demelza?" Marcus demanded angrily. "I thought you were more mature than that. That you're not just some little girl."

Demelza saw red.

Ordinarily that line would have calmed her down. She would normally be begging for his forgiveness at this point, trying to convince him that she was indeed mature enough for him, that she was more than just a young girl.

But now she could see it for what it was. How had she not seen it before? It was so obvious and yet she had fallen for it every time.

"I quit," she said in a low voice and Marcus raised an eyebrow and reached out towards her.

"What you going to quit honey?" he asked in a condescending tone and Demelza pulled away once more.

"I quit. I don't want to be your girlfriend anymore!" A look of surprise crossed his face and for the first time in what felt like a long time, Demelza felt her heart lighten. "I don't wanna keep secrets just to keep you. I want to be with someone who I can love openly. Someone who actually cares!" She paused as it hit her all at once. He actually did not care. At all. She was just a bit of fun on the side!

"Eh, it was fun while it lasted," Marcus said with a smirk. He leaned forward. "But at least I got to be your first."

Demelza angrily stormed away, barely able to see through the red mist that had descended across her eyes. Behind her she could hear him laughing as she left.

AN: I think I've captured the spirit of the prompt, but by all means tell me if I've missed something.