
I finished this manhwa on webcomics app sometime ago
Spoiler alert
It's just so fckn sad :( never expected such ending and I cried so much and I sometimes still think about the ending and feel like crying :( great story and plot twist though.

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At the end we get to know that
Zack was dreaming/hallucinating all this and he has repeated this hallucinations many times in his sleep/dream
Original Jason loved him but he left him and married and he even had a lil girl but after sometime when zack was hospitalized and jasons wife had died Jason asked zack to be with him but zack committed suicide and in after life he met ("hare"/jason of his imagination whom he loved and who loved zack like a psycho)
I feel bad for Jung :( i hope he finds someone too