In most cases, it might not be considered entirely appropriate within the school setting in fanfiction. Schools usually have rules about public displays of affection, and it can also be seen as a distraction to other students. However, in the context of fanfiction, which often bends the rules of the original world, it can be a way to show the intensity of their relationship.
It depends on how it's written. If it's written in a tasteful way that still adheres to the overall tone and values of the Percy and Annabeth story, it could work. But if it's overly graphic or just for the shock value, then it's not appropriate. Fanfiction should still respect the essence of the characters and not make them act out of character just for such scenes.
Well, from a storytelling perspective, while it might add some drama and show the closeness of their relationship, it can also be a bit controversial. Some readers might enjoy seeing that passionate side of their relationship play out in a school setting as it can be exciting. But others might think it goes against the more innocent or heroic image of Percy and Annabeth. It really varies from reader to reader.
Chapter 477, "Demanding Half The Stakes", is the clearest early answer because it turns Damien's situation into a concrete plot event. The setup is The courtyard was still echoing with disbelief over what had just..., but the pressure keeps building through He'd won and he needed to keep it that way..
Chapter 116, "Great Righteousness, Hunting Flood Dragons, Saliva [Five-in-One Mega Chapter]", is the clearest early answer because it turns Xia Chuan's situation into a concrete plot event. The chapter turns that into something concrete by moving from There are three large trees around, just barely reaching Teng Jiao's... to Can this saliva neutralize poison?" Covering their mouth and nose....
Chapter 459, "Camping In Another City", is the clearest early answer because it pushes Delwig into a new phase or setting. Early on, By the time they reached the city's outer gates, dusk had already.... By the end, The following day began with sunlight creeping through thin clouds..
Chapter 509, "So That's How It Works", is the clearest early answer because it turns Damien's situation into a concrete plot event. The chapter gives readers a real answer by opening on Hmm?" He has only begun his return back to where he'd laid waste to... and ending on Damien's fist slammed into its chest—harder than before, essence....
Chapter 435, "Finding Their Gate", is the clearest early answer because it turns Arielle's situation into a concrete plot event. It opens with The sky above Delwig's outskirts burned a dim copper. and closes on She crouched and brushed away loose soil with her hand.. The key payoff is that the chapter closes with Damien straightened slowly, eyes narrowing toward the ground.
Chapter 32, "Attack of the Cold Beast", 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 The small fire pit, after upgrading to an iron refining furnace, has... to Even though upgrading to an iron refining furnace doubles the daily....
Chapter 101, "The Excitement of New Clothes", is the clearest early answer because it turns Demon Sheep's situation into a concrete plot event. The chapter turns that into something concrete by moving from It's not that Xia Hong is particularly handsome. to Besides, clothing is not a particularly scarce resource.. What makes it stick is that the chapter closes with Shi Qing's son, Shi Ping., which gives Demon Sheep a stronger narrative position and pushes the power growth onward.
Chapter 394, "Fixing What She Ruined", is the clearest early answer because it turns Godsthorn's situation into a concrete plot event. Early on, The clamor of battle raged across the outer academy, and yet, within.... By the end, His face was solemn, his energy drained—but not yet exhausted..
Chapter 485, "Let's Hunt", is the clearest early answer because it turns Damien's situation into a concrete plot event. It opens with The moment Damien stepped out of the coastal forest and onto the... and closes on But the grass was moving wrong.. The key payoff is that the chapter closes with And Damien? Damien just smiled. "Let's hunt., which gives this chapter's turning point a stronger narrative position and pushes the power growth onward.