Gong Seung-yeonEun Yi-Soo Stephanie LeeDirector Park Kim Eung-sooHwan-Ki's father Kim Ye-ryeongHwan-Ki's mother Lee Han-wiRo-Woon's father Han Eun-seongJang Se-Jong Kim Mi-kyeongRo-Woon's mother Jang Hee-jinSeo Yeon-jung Kang Nam-gilBrain Security Seong Byeong-sukOrphanage director Jeong Dong-gyooInvestor in Brain Jo Hyun-sikMan at the men's restroom Kim Ki-dooMan at the men's restroom Choi HyukMan at the men's restroom Hur Young-jiYoung Gyu's transgender daughter Park Young-gyeHwang Yeong-Kyu Kim Dae-heeYeong Kyu's manager Choi Dae-chulRestaurant management Park Sang-myeonMaster Jin 
