Aphelios is one of those champions who at first glance seems utterly confusing. Admittedly, he has possibly the most strange and complex kit we've ever seen in League of Legends, but above all, he's a champion with a dual background, connected to other characters.
Lucian and Thresh have this kind of relationship, and the release of Senna a few weeks ago strengthened that storyline by introducing the character that connected the Chain Warden and the Purifier.
However, the situation is a bit different with Aphelios, since he is actually a dual champion and contains the lore of two characters. We learn this directly from his backstory, which you can find on Nexus.
"Born during a rare lunar convergence, when the physical moon was eclipsed by its reflection in the spirit realm, Aphelios and his twin sister, Alune, were celebrated as children of destiny by those of Targon’s Lunari faith."
Alune is Aphelios' sister, but she's not really in the game — or at least we can't really see her. Unlike Nunu and Willump, Kled and Skarl, Kindred and Wolf, or even Annie and Tibbers, Aphelios doesn't seem like a dual champion — but he is.
"When a match begins, Aphelios drinks poison to open a psychic(ish) connection with Alune. In order for her to speak to Aphelios and send him the magic-infused weaponry, she must be in her sanctuary fortress within the spirit realm. But the poison does more than create a connection. It fills Aphelios with the night’s power. His muscles tense, he can channel the magic—Alune’s magic. But not without sacrifice." (Source)
Aphelios' gameplay revolves around the connection he has with Alune. Each weapon that he uses is generated by his sister's powers, and Riot Games even gave justification to the randomness present in his kit.
"We were looking for a narrative justification for where the weapons came from,” says Riot Stashu. “Why does the player not get to choose which weapons they use? How does Aphelios get them? Why doesn’t this trained assassin monk have any control over it? Because Alune always knows what Aphelios needs."
A close relationship between two champions or characters is nothing new in League of Legends — Xayah and Rakan were designed around them being lovers, while we have known for some time that Thresh's lantern contained Senna's soul.
As surprising as it may have been, the eventuality of Senna freeing herself wasn't all that that crazy an idea.
However, considering Aphelios' gameplay and background, it appears highly unlikely we'll see Alune join our champion pools as a solo character. That would require a complete rework of Aphelios' kit, not to mention lore, since he doesn't technically own his weapons — instead, they are manifests of Alune.
This being Riot Games, though, we'd not rule anything out in the future!
We're not going to lie, the graphics of League of Legends are far from being the most realistic. One player had the good idea to recreate a realistic version of the Summoner's Rift thanks to Unreal Engine.