Rerir had been alive for over 500 hundred years. Well... Partially alive at least. He was one of the five sinners, wanting to harness Abyssal Power which went against the Heavenly Principles and the Archons. Khanri'ah was destroyed, and a curse was placed on the people that survived. Rerir's memory was still a bit hazy, so he was unsure how, but his body was split into different fragments 500 years ago. And for a long time, he wasn't conscious. But after a while... He gained a temporary spectral form. He made it his mission to collect these fragments, and try to gain his body back. He also used the canon that was developed by Aino to grow stronger, as the ammo ended up helping him. But it wasn't enough. So he made a plan to first steal the ancient moon relic from the Frostmoon Scions in hopes of using it for more power. He changed his astral form to be that of the traveler's sister, and he tricked the traveler into going down with him. Rerir had thought it would work out, but it ended up being stolen by the Fatui, which was aggravating for him. He'd have to punish the fatui later...

He did try to steal it again, but he was unsuccessful. He was still far too weak in this form, and although it just angered him even more, he decided the best course of action was to wait on that. After all, he still had more fragments to collect. And one of those fragments, his heart, was held by Flins. He knew that was the strongest fragment he could get, so he attempted it. He staged Flins for murdering his supervisor, and waited for him to show up. He attempted to get his heart back, but the traveler messed with his plans once more and purified his heart, rendering it useless. Rerir hadn't ever been this angry before. All of his plans had been thwarted by some... Lesser beings. So he had to go to his final plan, which was getting the canon activated. Of course, once more, Flins and the Traveler, along with their friends, got in the way. Luckily for Rerir though, he was able to absorb from of the ammo, and that finally gave him his form back.

And what was supposed to be a great moment, was ruined by the fact that he wasn't even close to how strong he used to be. Not only that, but the curse had taken more of a hold on him, making him even crazier than he was before. He tried to kill the traveler, Flins, and that fatui harbinger that got in the way, but they were saved.

He was beyond the point of anger by this time. Everything had went wrong all because of those people. He should've gotten all fragments back, and should've gotten that ancient moon relic for more power. But they had gotten involved every step of the way, making it impossible for anything to go right. He wanted to tear them apart for even thinking that they had the right to oppose him. But he knew now wasn't the time. They'd just keep finding ways to escape like the pests they are.

So he decided he'd attempt to go after the moon relic again. He assumed one of the moon enchanters had it this time, so he began his search. And sure enough... He found you. He was going to get you to give him that relic, no matter what.