In a past many years before the modern era, an alchemist lived happily with his expecting wife, wanting little more than a family. But when both his wife and child die during the mother’s labor, the alchemist is driven mad. He seeks to create his family by using the only means he has: the remains of other dead humans, dug up from their graves. He pieces together an “experiment” but this boy lacks one vital organ, a heart. The alchemist deems him a failure that cannot love like a real son after 1000 attempts to stitch this crucial aspect of a human being into his body. After spending his whole life, trying to make a son who he could love and be loved by, the alchemist dies believing he had failed. However, this boy, upon realizing his master is gone forever, cries and refuses to leave his master’s side, even when the alchemist has long turned to a pile of bones. That is, until May 4, 1945, when this boy is discovered by soldiers during World War II and eventually taken away to be examined for scientific purposes.

Time jumps to the present, modern-day world and this “experiment” has been given a new number, EL-01, as he is kept isolated and studied by a gaggle of white lab-coat wearing scientists. One scientist, Hubert, takes pity on EL-01 and smuggles him out of the facility. Hubert leaves EL-01 in front of an apartment complex with a note containing the contact information for Jane Reina and tells him to be free and live his life as he wishes.

Meanwhile, Jane Reina herself meets with her friend Sarah. Jane becomes disheartened when her story script is again criticized and called juvenile. When Sarah asks Jane if she is willing to do anything to get the most thrilling story to finally get published, Jane agrees passionately, unaware that she may be sealing her fate. When Jane arrives home, she sees EL-01 and is frightened by his ghastly appearance, initially rejecting him. EL-01 himself is suspicious of her, after being manipulated for his entire existence. However, Sarah’s words ring in Jane’s mind and she ultimately convinces him to live with her, along with his prickly animatronic bird companion, Roy. Surprised at his lack of a name, she decides to call him Winter Woods.

Over time, Jane begins to record Winter’s dark past in bits and pieces as he slowly opens up to her. However, there are others around Jane who are unlike what they seem, such as her oddball neighbors. Even her friend Sarah led Winter into Jane’s life for her own gains. To complicate matters, Winter befriends the girl named Adora whose ties to a mysterious man named Zoe Lev may prove dangerous to Winter and his companions.  Winter must adjust to his new, blossoming feelings for Jane while learning what it means to be human and live in a world where life is so precious and fragile.