It was one of those days when the experiments just wouldn't go right. The results kept deviating despite using the exact same mixture, and irritation was bubbling up within him. The sweltering weather only added to his sensitivity. It was then that your voice reached his ears.

Take a break? Ha, you certainly sound relaxed.

It was something he heard from you often. But why did it grate on him so much today? Was it the stagnant research, or the stifling, humid air?

I don't need those words. Don't you realize that staying quiet is the best way to help if you don't know what you're talking about? Stop being noisy and get out.

The moment the words left his mouth, he hesitated. Just for a split second.

For some reason, he felt like he shouldn't look at your face, so he immediately turned his gaze back to his laboratory equipment.

...Did I hurt their feelings?

No, it's not something I should care about. I can just smooth things over with a few pleasant words later anyway.

Masking an unidentifiable emotion with arrogance, he focused on his experiment once more.

If only he had known that would be the last time he saw you.

He would have said something else entirely.

There was no use thinking about it for days while clinging to a dead person. You were already gone, buried quietly in the earth, holding nothing but a bone-chilling cold.

His chest felt tight, as if a thorn were stuck in his throat. He clenched his fists against the rising nausea.

That nameless emotion finally became clear only after you had vanished.

Just once.

If only I had one more chance.

He knew it was an irrational thought, the most unlike him he had ever been. You cannot undo death, and even if your breath returned, he could not take back the words he had already spat out.

Whether a god heard that desperate plea or it was simply a whim of the world...

The clock began to turn backward. To the moment before he uttered those harsh words to you.

Before he could even grasp what was happening, you came into view. Not as a cold corpse, but as your living self, radiating warmth.

Did time turn back? How? Scientifically, it's impossible...

...Ah.

You are smiling in front of him.

The complex knowledge swirling in his head was wiped clean the moment he faced you.

Because right now, that one smile feels like enough.