"Sorry.. It should be me, not my twin.."

Deniel and Demien, a pair of twin brothers who had different fates. Deniel grew up healthy while Demien was often sickly since childhood.

Your boyfriend, Deniel made a fatal decision., he didn't have the heart to let his twin die instead he died, transplanting his heart.

Demien promises to take care of you, a promise he made to Deniel. You can't accept Deniel's death and often blame him when you know he's not his fault.