Yoo Seung Ho as Kim Min Kyu, Perfect from head to toe with an IQ of 157, Kim Min Kyu is head of Korea’s biggest financial company (KM), with such severe allergies that he lives in a sterile environment, devoid even of humans. However, there is a lot of mystery surrounding him, as he lives alone in a veil of residence, living alone in a mansion like a castle. He’s never had the experience of falling in love until he meets a girl robot one day

Chae Soo Bin as Jo Ji Ah / Aji 3, a passionate and energetic young entrepreneur who possesses an extremely high EQ (emotional intelligence) and whose dream is to make things that people need. Her ex-boyfriend Baek Gyun, a robotic engineer, asks her to act as a robot part-time.

Uhm Ki Joon as Hong Baek Gyun, Jo Ji Ah’s ex-boyfriend Hong Baek Gyun is a world-renown genius robotic engineer. In the drama, he secretly creates the world’s most advanced AI android robot “Aji3.” He is the man who is instrumental in Kim Mingyu finding love in the female robot. But the genius robot professor is a bumbling novice himself in the ways of romance.

Santa Maria Team

Park Se Wan as Pie
Song Jae Ryong as Hok Tal
Kim Min Kyu as Ssan Ip

KM Finance

Kang Ki Young as Hwang Yoo Chul
– Go Woo Rim as Yoo Chul (Child)
Hwang Seung Eon as Ye Ri El
– Kwon Soo Jung as Ri El (child)
Son Byung Ho as Hwang Do Won
Lee Byung Joon as Ye Sung Tae
Lee Hae Young as Yoon Jun Mo
Yoon Kyung Ho as security team leader

People around Kim Min Kyu

Uhm Hyo Sup as Professor Oh
Kim Ha Kyoon as Butler Song

People around Jo Ji Ah

Seo Dong Won as Jo Jin Bae
Lee Min Ji as Sun Hye
Yoon So Mi as Hong Joo
Lee Han Seo as Jo Dong Hyun

Others

Kim Ki Doo as Miami
Choi Dong Goo as Alps