A Promise: That would surpass even the dimension of time

Two lovers are reincarnated after they meet their horrible fates in their previous lives, given the chance to once again spend their time together.

In the rule of the terrible dictator Adolf Hitler, death was the scent that surrounded him, so much so that even Death himself avoided him many times. 

He tortured people, murdered them, severed them apart from their families, experimented with them, and the list would go on and on. 

Among those people whom he oppressed, there was John and Heather, who have been hiding from the Nazis by moving from house to house to avoid the inspections. They hated this kind of life, having to run every day and every night just so they would not lose the two things they cherished the most, their lives and each other. 

They did not believe in such a thing as luck, and for it to run out on such people is a cruel verdict. 

One fateful evening in their usual attempt to evade the authorities Heather trips on a large fallen branch, spraining her ankle, all while she lets out a shriek of painful proportions. They hear the footsteps of the running military personnel coming towards them as they feared for their lives.

'Heather! I can help you up.' 

'No, John. At this rate they will catch both of us. Please, leave me and run for the next town.'

'But..but-'

'Please, John! I'm begging you!'

'No! I will never leave you, Heather. I will have drawn my last breath before I ever leave your side', John reassures her while tightly grasping her hand, trembling both from the cold of the evening and from fear taking over. 

Lights flash towards them, temporarily blinding the both of them. Guns were pointed to both of them as the military proceeded to separate them. 

Tears fall from both John and Heather's weary eyes. 

'Listen to me, Heather. I will always be by your side, I will always be yours. Whether in this life or the next, I will think only of you, I promise you that.' He struggles to hold on to Heather's freezing hand.

'Joh--n! I- I-..!'

And he could do nothing but watch as they take her away from his grasp, leaving him alone with two other officers. 

They are brought to different camps. For experimentation, for slavery or torture, no one knew. But one thing was certain in John's mind, that he would never see the love of his life again, as he and his group of frail and cold companions were now being sluggishly led towards the infamous gas chambers. Their life was now limited to the steps it would take to reach that particular chamber. 

'I am sorry, my love,' as he steps into the cramped room and the door is locked behind them.

Most of the people he was with screamed and kicked on the firmly locked door, while some knelt down and summoned what remained of their strength and desperately called for the deities that they so wholeheartedly believed in. 

But John was quiet, staring at the nozzle from which the poisonous air would be released from. 

'It seems my words to you may have been futile, Heather. But my last words, though few as they are, will be of utter importance. I hope that wherever you are right now you are listening.'

A small fizzle-like noise comes out of the valve bolted on the walls. Their wretched arbiter has arrived.

'I love you, Heather. Now and always.'

He closes his eyes, falls downward on the freezing floor, and breathes his last. 

In the distant year of 1990, a young man named Mark awakes.