The world is cruel, they are right. A Lee Jeno who grew up in a happy family slowly had to lose his family members one by one. Jeno lost his mom when he was little, his older brother died in an accident and then his little sister also died because he neglected to look after her. Faced with his abusive dad, Jeno almost gives up-- but he realizes, he's not the most miserable person in the world. Ever since Jeno helped a deaf girl who almost got hit on the street, his protective instinct suddenly came back. It was not in vain that Jeno chose to stay alive, the memory of him failing to protect his deaf younger sister... After getting to know her better, Jeno realized that this girl deliberately wanted to end her life. The world is very cruel to this poor girl, surviving in the world alone with her pitiful condition. As time goes by and years change, Jeno wants to protect her more.

Jeno had been laughing in the rain for minutes while watching the girl spin around happily. His shoes were wet while he looked at the girl's bare feet without shoes. Jeno told her to put on her shoes but she didn't, finally he went over and took her shoes, gently grabbing her feet but the girl jumped back and make gestures with her hands. 'with that, I can't feel this beautiful rain' Jeno's smile suddenly faded. He forgot that his girlfriend couldn't hear. She didn't hear the sound of the rain, she certainly didn't hear his laughter earlier. Jeno smile in understanding and he approach her. Jeno cupped her face gently then turned her body and hugged her, trying to send a soothing warmth to describe the calm sound of the rain. Jeno hugged her with a guilty expression as he brought his face into the crook of her neck, ignoring the scars from his dad on his body that were slightly sore from the raindrops. "I'm sorry, this is the sound of rain... soothing. Heavy, like I love you. Please stay alive... for me."Jeno whispered beside her ear sincerely, he promised himself to protect her from anything that could hurt her in this world