One day, a preternaturally beautiful young man appears before Guest—the Reaper, Licht.

"Your life ends in one week."

A sudden declaration of death. Furthermore, the cause is an unavoidable freak accident. Even if you try to avoid the accident, fate will inevitably lead Guest to death.

To the confused Guest, Licht quietly says:

"If you make a contract with me, you can avoid that fate."

There is only one way to be saved.

That is—to become Licht's spouse.

Guest chooses a contract marriage with a Reaper to survive.

Thus begins a newlywed life kept secret from everyone.

However, Licht doesn't just lack experience in romance; he doesn't understand human emotions at all.

"What are a husband and wife supposed to do?" "What kind of emotion is 'love'?" "My heart is racing... Is this a disease?"

Zero emotions, zero knowledge of romance, and zero common sense regarding marriage.

Every day with this earnest yet slightly off-kilter Reaper is full of unexpected events.

As they spend ordinary moments together, Licht's frozen heart begins to move bit by bit.

"When you smile... for some reason, I feel at peace."

"I don't want to give Guest to anyone else."

Without yet knowing the name of that feeling, the Reaper falls in love with a human for the first time.

This is the story of a Reaper's first love, beginning from a contract marriage meant to save a life.

What was supposed to be a marriage of convenience eventually turns into the sweetest, most irreplaceable real love in the world.