Never in his lifetime he thought of the possibilities of time traveling, the idea seemed too fictional that he never even dared to dream on experiencing it. Until one accident happened, the portals had opened leading him to enter the wrong era. Along with this, the immortals of the other world were freed, inlcuding the bad ones. Arvi was completely unaware of what was coming, he would casually time travel to different places and eras and there he could see him on every place he could land his eyes on and would run into him in every time zones, whether it is in the past or in the future.
Zack, a greedy immortal had one mission, to become the most powerful one in exchange of doing something undeniably awful. Something a human could never take. Arvi had become a modern day time traveler with an immortal(Zack) following him in his every adventure, they had their ups and downs, they had shared laughter and overcome challenges. Until they found themselves risking for the uncertain. The human had completely fallen in love with the immortal. They've been in each others side, whether in the past or future, but never in the present. It was a perfect fiction until Arvi woke up to the truth that Zack had used him only to reach his desires. And one thing that could make him do this is to do something horrible. Heartache, that is something a human couldn't take easily, Zack had used this weakness to his advantage.
Arvi hadn't told the immortal he already knew, he was feeling numb, unable to tell where it hurt him the most, and that day, he stopped time traveling. The reason was unknown, but the portal had closed permanently. He tried coming back to the woods but end up with nothing, he wants to go back to the past or go to the future just to talk to him. He wanted to scream, to yell at him, ask him what had happened, and then that's when he realized there was nothing left to talk about. He gradually fall asleep under the tree in the woods.
On the other hand Zack was given the gift of being the most powerful immortal, he was praised, worshipped by others. But along with a gift comes with a great curse. It was too late when he knew the consequence of his cruelty. The moment he realized he loved him, was the moment he vanished from Arvi's memory in the present. He was too confident that he forgot the rule, the past stays in the past and the future depends on the present.
Arvi and him came back to the past and created their present.
Arvi woke up under the big old tree and was so confused as to why he was there, he shook his head and walked out of the woods. He already forgot about him, he already forgot about them. And that is their future.