I wasn't gonna update more of this, but I got a review with a suggestion so I decided to do a bonus chapter. I may do more of these but no promises
Disclaimer: I still don't own any of these characters or franchises.
Strictly speaking, legends don't interact outside their canon.
The reality is: of course they do. Immortals are basically a bunch of old ladies: everybody knows everybody else and is into everyone's business. Shameful gossips the lot of them.
Within the pantheons Western Civilization has acquired over the years (and given that Western Civilization has a tendency to drag other cultures into metaphorical dark allies, beat them into submission and rifle through their pockets for spare ideas often forgetting context all together; this actually works out to quite a few displaced gods) someone on Olympus was bound to hear about the newest Guardian eventually.
Well, quite a few somebodies actually. It was just a matter of whether they would do something about it or not.
Thanatos
The Son of Poseidon appeared on his list for a brief moment before disappearing again. Thanatos blinked slowly, mildly confused. People did not just disappear off his list when he was called to collect them.
He flew towards the destination he had seen on his IPad, swift as he could, appearing unnoticed and uninvited as Death sometimes can.
He was just in time to see the new Immortal fly off into the moonlight. He slipped off to his next task, question answered.
Death would not be collecting Perseus Jackson's soul today.
Eros
He's been here since the beginning and likely he'll be here until the end. In this age of modernity he goes by Cupid, though he can't quite figure out how the humans figured him to be an underdressed baby with wings. But whatever, he'll take what he can get. He doesn't have much pride.
His "Mother" (Aphrodite isn't really and he's older than she, but it's been so long that she believes the pretend game they've played for years. It annoys his wife Psyche like nothing else) wails about the loss of her 'perfect little love story'.
Eros shakes his head. Wasn't it supposed to be tragic, the story of Percy and Annabeth? That's what she wanted anyway. Eros feels for the young Daughter of Athena, he really does (being separated from your love is never a kind feeling) but really? Eros doesn't think it was a good match. There was potential for an interesting story sure, what is a hero without a love interest, but Eros thinks Percy Jackson could have done better.
He's fairly positive Annabeth couldn't have.
He's the God of Love, and in this modern age, Love in all its forms. So he sees a little more, hears a little more and -because he gets to be among the mortals most often- learns a little more than the Olympian Council.
When he's called to Council of Great Spirits, he sits next to Mother Nature and overhears Nicholas St. North mention something about an Angel-boy to the Sandman, who sneaks a look at him.
He vows to check it out. And is a little surprised by what he finds.
He smiles a little to himself at the Guardians Boxing Day Party that the Great Gods of Olympus would never deign to attend (though he thinks he sees Hera in the corner) as he watches the Winter Shepard feed the Hero of Olympus a piece of cake.
Much better indeed.
Hera
He looks so like her brother. That's the first thought the Queen of the Gods has when she sees the newly immortal Percy Jackson for the first time. The second is that immortality has not dulled his tongue any. She is surprised how much that relieves her.
He doesn't remember her. Or his father. His friends. His family. Everything before is blank. He only knows he must protect the Demigods. She smiles sadly. She is the Goddess of Family and even if she isn't perfect, even if she doesn't like her husband's other children, even if she doesn't approve of demigods in general, she is still the Goddess of Family. And the demigods are family.
That's why she didn't fight the decision on Olympus at the end of the Titan War. The demigods are family and the more together the family is, the stronger she becomes. She may jealous, callous and occasionally wrathful, but she tries to have very little to do with demigods because they are mortal and they die.
And now Tsar Lunar and the Fates have wrought something that will protect them. That will give them a chance at life. And that something is her favorite nephew, who will not be joining her eldest brother in his kingdom anytime soon. So she feels safe and allows herself to mother him a bit. She hasn't let her more maternal instincts out in centuries and it's strangely gratifying to do. She smiles softly, combs his hair and smiles more viciously when she realizes her family's actions have definite consequences.
He'll remember when the time comes and Hera knows not to interfere in another's game.
Artemis
The first time she saw him, he stood like a statue, wings forming a protective embrace around her newest huntress. She blinked, surprised at this show of hostility. Then she realized none of her girls could see him, the new recruit included.
She asks the new girl for her tale, intrigued by him and watches him nod at the girl's wonder at some of the miracle. But his eyes stay on her, silently judging her worth. When the girl takes her vow and she accepts, his eyes flash with a fleeting recognition before he turns to leave, no longer needed.
Just before he exits the tent he turns to look at her again. She nods, acknowledging him. Surprise flashes across his face before he bows slightly to her and leaves.
Artemis lets him. She knows it will not be the last time she sees Perseus.
Poseidon
Angel, they tell him, Guardian Angel.
Poseidon doesn't believe in coincidences. Something is protecting the demigods. And then he hears more stories; stories that start to give him an idea of just who that something might be. The Angel looks like him, the little ones say because they can see him the most clearly. The Angel has his hair and eyes and smile.
It should be impossible. His son turned down Immortality. (Godhood, whispers a voice in his head, your son turned down Godhood and you of all deities should know that it is not the same thing.) And yet, it is impossible for it to be anyone else. His son is not in Hades' kingdom. Somehow, his son ascended to Immortality.
The day his son comes home, he weeps unashamed tears of joy.