One common theme is the struggle between Conner's heroic nature and the Vampire OC's more primal instincts. It often creates a lot of internal and external conflict. Another theme could be the Vampire OC trying to fit into Conner's world of superheroes and justice, while hiding their true nature.
Many of these fanfictions explore the theme of identity. The Vampire OC may be trying to find their place in a world that doesn't fully accept them, and Conner might be dealing with his own identity issues as a clone. Their relationship can be a journey of self - discovery for both of them. There can also be themes of loyalty, as they face challenges that test their loyalty to each other and to their respective 'sides' - whether it's the vampire community or the superhero team in Young Justice.
Chapter 659, "Bodyguard Agreement", is the clearest early answer because a shaky connection becomes usable in the plot. The chapter gives readers a real answer by opening on Besides, how easy is it to get into the Gu Family? and ending on The woman who had defeated him and taken all his hopes..
Chapter 498, "How can someone be so ugly?!", is the clearest early answer because it turns Ren Yue's situation into a concrete plot event.
Chapter 374, "From Now On, Jiang Li Calls the Shots in Golden Sand!", is the clearest early answer because it turns Jin Siyue's situation into a concrete plot event. It opens with Jiang Li's bold behavior infuriated Jin Siyue, but it also succeeded...
Chapter 738, "Here to Fight!", is the clearest early answer because the buildup finally cashes out in a real clash. The chapter turns that into something concrete by moving from Feeling that something was amiss, he immediately called Jiang Li.
Chapter 444, "Wait and See", is the clearest early answer because it turns Shang Shuyue's situation into a concrete plot event. It opens with Carrying a backpack, Yu Li walked for over ten minutes but ultimately...
Chapter 719, "Borrowing Their Luck", is the clearest early answer because it turns Ye Chu's situation into a concrete plot event. A useful checkpoint is the way the scene starts with Chang Rong: "Hmph, it has nothing to do with me anyway, since no one...
Chapter 692, "My Ideal Type is Assistant He", is the clearest early answer because it turns Do's situation into a concrete plot event. The chapter turns that into something concrete by moving from Zhao Lang's gaze stayed fixed ahead as he gripped the steering wheel...
Chapter 569, "Watch How My Sister Torments You!", is the clearest early answer because it turns Ai Xiaochun's situation into a concrete plot event. A useful checkpoint is the way the scene starts with Due to the unequal number of members on Team J and Team Q, the system...
Chapter 645, "Without Luck, You Are Nothing!", is the clearest early answer because it turns Shang Shaojing's situation into a concrete plot event. The chapter gives readers a real answer by opening on Shang Shaojing furrowed his brow and fished out two banknotes from...
Chapter 415, "No Food, But Your Life", is the clearest early answer because it turns Jiang Li's situation into a concrete plot event. The chapter gives readers a real answer by opening on Are you begging me for food now?