In the series, Song Kang played the character of Jeong Gu-won, a 200-year-old demon who makes evil yet sweet deals using human souls as collateral, establishing himself as a top predator in the chain of the living. His life takes an unexpected turn when he encounters Do Do-hee (Kim Yoo-jung) and falls in love with her, a mere insignificant human. Their passionate romance and onscreen chemistry was so high that fans were hoping something brewed between them in real life. It was further fuelled by their Best Couple Award at the 2023 SBS Drama Awards. 

Now, as the show ended, the actor shared his heartfelt thoughts and stated, "The time has flown by, and now 'My Demon' has ended. As with all my works, I filmed 'My Demon' with happy memories, and I am always grateful for the love it received. I am happy and thankful for the memories created during the long period of about 7 months. I will treasure the affection, support, and interest sent by the viewers and fans. I hope you will remember and love 'My Demon' for a long time. Thank you!"

Fans also poured in well-wishes for the actor. One tweeted, "Thank you, Kang, for the wonderful gift before enlistment. I'm happy to see Guwon becoming one of the favorite kdrama characters. Your hard work is appreciated, and you will be dearly missed. I'm so proud of you! Serve well and take care!" While another wrote, "he shone so beautifully in this role and i think it’s so special that such an impactful character and project are seeing him off." A third one commented, "no im gonna cry i just realised he’s leaving for the military." 

With an end to 'My Demon,' the horror-thriller drama 'Sweet Home Season 3' will be his last project before he enlists for his mandatory military service. The date of the enlistment will be announced soon.