Disclaimer: Don't own any of it. Covenant and Percy belong to their creators
Few know that the Gods of old really existed and even fewer know that they still exist and have children with mortals. And that those children are incredibly powerful. Especially in the case of one. Who even without the Godly parents would be powerful. Thanks to an old Covenant. Grayson Garwin met and fell in love with five unique individuals when he was traveling.
They were Strife, God of Mischief, Chaos and Mayhem. Who was created after the defeat of the Titans. There was so much discord energy that it caused Eris, Goddess of Discord to overflow with power. Which needed to go somewhere and it did, into a child. A child that was of all Gods and Titans. Strife became the second in command to War and was beyond powerful that instead of the Twelve it became the Thirteen. The second was Zeus, King of the Gods. The third was Poseidon, King of the Sea. The fourth was Hades, Lord of the Dead and the fifth was Nyx, Goddess of Night .
The six of them came together for over three years and together created a child. A child of them all. And they were happy and in love. Then, in 1989, Kronos came back and the Gods had to leave to fight him.
Leaving Grayson and Reid alone. Trusting in Grayson's power to protect them now that he was free of the aging, but Grayson was no match to Kronos who came himself to kill a very big threat to him..... Reid. Grayson died but managed to alert Nyx who rescued Reid.
After that Nyx took the form of Elena Garwin, Grayson's 'wife' and lived in Ipswich. Raising Reid with his Covenant Brothers who knew nothing of his true heritage or who his 'mom' really was. Time moved on after Grayson's death and eventually Reid was able to move on, largely due to his mom's and fathers help. And when he turned eleven he began to go to the Camp in the summer.
Something that caused the other Covenant members, both his Brothers and their parents to question and caused Nyx/Elena to explode. Telling them that Reid was her son and if they didn't leave it alone, she would take him and leave. And then where would their precious little Covenant be? They quickly backed off after that.
When Reid got his Covenant powers he found them fascinating and used them for everything. Which caused everyone of the Covenant to worry. After all they didn't know the aging wouldn't affect him. They began to hound Reid to stop until finally he left and went to the Camp and stayed there for almost a year.
It was there that he truly met Percy and Annabeth. The three of them started a relationship and were quite happy. Eventually though Reid wanted his Brothers though so he returned and they were so happy to have him back that they stopped hounding him.
Time moved on and they grew up and Reid continued to have two separate lives and was quite happy with that. Until his seventeenth year and Chase came along. After that everything changed. Caleb's Ascension was beyond the normal thanks to Chase and Caleb's father. It caused Caleb to go after what he desired, which was Reid.
His power caused them to have vastly wild and passionate sex. And unknowingly to them, Pogue walked in on them and watched for a while before leaving. Afterward, which was two days later, they actually talked and Caleb admitted to his true feelings, which was his love to Reid. Reid admitted to loving Caleb but then admitting to being with Percy and Annabeth, who he had never spoken about. It left him at an impasse as now Reid knew what it was like to be with Caleb. He didn't know what to do so he went to Olympus to hide and think.