Sera and Heeju are identical twins, but no one confuses the two. Sera is beautiful, bright, and charming, while Heeju is dirty, smells bad, and has no charm at all. Heeju became this way due to the abuse and discrimination she suffered from her mother since childhood. Because of that, Heeju's soul gradually withered, and she got used to the idea that "it's all your fault" for being so insignificant. Until one day, when Heeju, after accidentally finding a lost dog, gets closer to Grandma Myungja. Thanks to Grandma Myungja, who sees her without prejudice, Heeju begins to experience a new phase in her life...