God of Ad-Lib / 애드립의 신 Lee Tae-gyu, a 30-year-old NEET. At some point he lost the ability to feel emotional highs and lows, drifting through life in a state of listless numbness. While struggling to escape his meaningless routine, he meets a mysterious old man and gains the “will-o’-wisp ability” to copy the emotions of others. While testing this power, he becomes entangled with drama writer Kwak In-ho, and from that meeting his life begins flowing in an unexpected direction — toward acting, a path he never once imagined for himself. “Improvisation? I’m the best in the world at it.”