Per wiki policy, Spoilers Off applies here and all spoilers are unmarked. You Have Been Warned.
Seiya is going to become a god himself
It's noted that the primary things seperating Seiya and Rista from being together is the taboo that humans and deities can't be romantically involved, and that whenever Seiya saves a world he's gonna be sent back to Earth and risks losing his memories. However, it's established that deities can be borne of humans, with two prime examples being Cerceus, a human warrior reborn as the "Divine Blade", and Ristarte, the human princess Tiana and Seiya's lover reborn as the Goddess of Healing. Since both Seiya and Rista are fully aware of the fact they have a Reincarnation Romance but can't be together due to the taboo, something will happen that will kill Seiya and prevent him from being sent back to Earth, possibly overusing the Berserk skill, only for Ishtar to help out by reviving Seiya as a deity himself, allowing him to be with Rista and not worry about the taboo. While they may run into the problem of him not remembering his human identity much like Rista & Cerceus couldn't remember theirs, he should be able to regain his memories much like Rista regained hers. His title as a god will be "God Of Preparation" and, as such, he will have a Note to Self, explaining everything. After the ascension, Rista will ask him if he remembers her, and he will say something like, "Of course I do, inferior herb woman".Colt was reborn as a God
If Aria praying for Tiana combined with her good deeds was enough to get her reborn as a Goddess, why couldn't the same have happened to Colt? It's clear Aria cares deeply about Rista and was made aware of her past identity as Tiana, so it's just as possible her grief for Colt combined with his deeds let him be reborn as a God too.