It's possible that the gods might step in to save Percy. Zeus, despite his usual aloofness, might see the threat that Gaea poses and send a bolt of lightning to drive her away from Percy. Or Poseidon, being Percy's father, could use his powers over the sea to flood the area where Percy is being tortured, washing Gaea's influence away.
His other demigod friends from Camp Half - Blood could also come to his aid. For example, Jason with his ability to control the winds could create a powerful gust to blow Gaea's attacks away from Percy. And Piper could use her charm - speak to distract Gaea long enough for Percy to escape.
Annabeth could be the one to come to Percy's rescue. She is very intelligent and resourceful. She might figure out Gaea's weaknesses and use that knowledge to free Percy.
Annabeth might try to find a way to get to him. Their relationship is very strong, and she's not one to just leave Percy in danger. She could use her intelligence to figure out a way to enter Tartarus and help him escape.
Annabeth could be a likely candidate. She's always been by Percy's side, and she'd stop at nothing to save him. Her intelligence and combat skills would be useful in the dangerous environment of Tartarus.
Chiron could also be a key figure in trying to save Percy. As the centaur trainer at Camp Half - Blood, he has a lot of knowledge and connections. He might try to negotiate with the gods on Percy's behalf or find some loophole in the gods' actions to free Percy.
Perhaps Gaea uses Percy's own insecurities against him in this fanfiction. She might dig into his fears about not being able to protect his friends and family. By constantly whispering these fears in his mind, she could mentally torture him. This could be combined with physical torture, like having him trapped in a dark, claustrophobic space underground, which would heighten his sense of helplessness.
Chiron, the centaur mentor at Camp Half - Blood, might get involved in the rescue. He has a vast knowledge of the demigod world and could use his wisdom and connections to track down Luke and free Percy. Also, some of the other demigods at the camp who look up to Percy might volunteer to help, like Clarisse. She may not like Percy much, but she wouldn't want a fellow demigod to be in the hands of Luke.
It could be Ares. He's always been sort of a hot - headed and war - loving god. Maybe he's jealous of Percy's popularity among the demigods and wants to see him suffer. So he manipulates the other gods into believing Percy has done something wrong and that he should be tortured.
Annabeth would most likely be the first one to try to rescue Percy. She and Percy have a deep connection, and she wouldn't stand by while he's in danger. She's smart and resourceful, so she'd come up with a plan to find out where Aphrodite has taken him and then figure out a way to get him back.
Well, it's not as popular as some other pairings in the Percy Jackson fandom. Gaea is a major antagonist in the series, and the idea of her in a romantic relationship with Percy is rather unorthodox. So, compared to more common pairings like Percy and Annabeth, it has a much smaller following.
It could be the traditional villains from the original story, like the Titans or some powerful monsters. They might torture Percy to get information or just to cause chaos.
Percy would likely be more ruthless. Gaea's influence might make him less hesitant to use force or manipulation to get what he wants. For instance, he might not be as concerned about the well - being of mortals as he was in the original story.