Dear X

Jo Hyeon-jin (Sim Sung-hee's Mom), Bae Soo-bin (Baek Seon-gyu), Lee Seo-an (Lim Sun-ye), Gi So-you (Child Baek Ah-jin), Kang Ian (Art Teacher), Kim Yi-kyeong (Sim Sung-hee), Yoon Joo (Class Teacher), Kwon Su-yeon (Yu-bin), Shin Eun-hye (Ga-yeong), Woo Doo-yeon (Ethics Teacher), Park Hoo (Child Yoon Jun-seo), Ma Jeong-pil (Sim Sung-hee's Dad)

Bae Soo-bin (Baek Seon-gyu), Lee Seo-an (Lim Sun-ye), Gi So-you (Child Baek Ah-jin), Kang Ian (Art Teacher), Kim Yi-kyeong (Sim Sung-hee), Kim Ji-hoon (Choi Jeong-ho), Kim Ji-young (Seo Mi-ri), Hong Bi-ra (Moon Do-hui), Jeon Kuk-hwan (Jun-seo's Grandfather), Son Kang-gook (An Do-gang), Kim Il-woo (Hong Su-hyeok), Kim Yu-mi (Hwang Ji-seon)

Bae Soo-bin (Baek Seon-gyu), Kim Ji-hoon (Choi Jeong-ho), Baek Sun-ho (Xanadu Coffee customer), Kim Ji-young (Seo Mi-ri), Hong Bi-ra (Moon Do-hui), Jeon Kuk-hwan (Jun-seo's Grandfather), Lee Seung-jin (Detective), Kim Sang-il (Im Seung-yong), Kim Il-woo (Hong Su-hyeok), Kim Yu-mi (Hwang Ji-seon), Park Seung-wan (Jo Yoo-sik)

Kim Ji-hoon (Choi Jeong-ho), Hyun Seo-ha (Seok Hyang-i), Kim Ji-young (Seo Mi-ri), Shin Mun-sung (Park Dae-ho), Hong Bi-ra (Moon Do-hui), Kim Se-yoon (Detective), Kim Yu-mi (Hwang Ji-seon), Kim Jae-il (Internal Affairs Officer), Park Seung-wan (Jo Yoo-sik)

Hwang In-youp (Heo In-gang), Hyun Seo-ha (Seok Hyang-i), Kim Ji-young (Seo Mi-ri), Shin Mun-sung (Park Dae-ho), Hong Bi-ra (Moon Do-hui), Jeon Kuk-hwan (Jun-seo's Grandfather), Choi Sol-hee (Jae-oh's Aunt), Kim Il-woo (Hong Su-hyeok), Kim Yu-mi (Hwang Ji-seon), Son Gun-woo (Director), Seo Hye-jin (Staff)

Hwang In-youp (Heo In-gang), Park Seoung-tae (Heong Gyeong-tae), Hyun Seo-ha (Seok Hyang-i), Kim Ji-young (Seo Mi-ri), Shin Mun-sung (Park Dae-ho), Hong Bi-ra (Moon Do-hui), Ryu Kyeong-hwan (Im Hui-guk), Yoon Hyun-soo (Ryu Ji-hyeok), Lee Woong-jae (Heo In-mo), Son Kang-gook (An Do-gang), Kim Yu-mi (Hwang Ji-seon), Cho Mi-yeon (Host)

Kim Yi-kyeong (Sim Sung-hee), Kim Ji-hoon (Choi Jeong-ho), Hwang In-youp (Heo In-gang), Park Seoung-tae (Heong Gyeong-tae), Hyun Seo-ha (Seok Hyang-i), Kim Ji-young (Seo Mi-ri), Hong Bi-ra (Moon Do-hui), Jeon Kuk-hwan (Jun-seo's Grandfather), Ryu Kyeong-hwan (Im Hui-guk), Lee Woong-jae (Heo In-mo), Kim Yu-mi (Hwang Ji-seon)

Kim Yi-kyeong (Sim Sung-hee), Kim Ji-hoon (Choi Jeong-ho), Hwang In-youp (Heo In-gang), Park Seoung-tae (Heong Gyeong-tae), Jung Woo (Seol Yeong-uk), Kim Ji-young (Seo Mi-ri), Hong Bi-ra (Moon Do-hui), Ryu Kyeong-hwan (Im Hui-guk), Hong Jong-hyun (Moon Do-hyeok), Lee Woong-jae (Heo In-mo), Kim Yu-mi (Hwang Ji-seon), Kim Min-song (Tattoo Man)

Kim Yi-kyeong (Sim Sung-hee), Kim Ji-young (Seo Mi-ri), Hong Bi-ra (Moon Do-hui), Ryu Kyeong-hwan (Im Hui-guk), Hong Jong-hyun (Moon Do-hyeok), Son Kang-gook (An Do-gang), Kim Il-woo (Hong Su-hyeok), Kim Yu-mi (Hwang Ji-seon), Kim Min-song (Tattoo Man), Kim Nam-hee (Documentary Host), Kim Kyu-do (CEO of Dio Entertainment), Oh Jae-se (Detective)

Kim Yi-kyeong (Sim Sung-hee), Hong Jong-hyun (Moon Do-hyeok), Son Kang-gook (An Do-gang), Kim Il-woo (Hong Su-hyeok), Kim Yu-mi (Hwang Ji-seon), Go Seo-hee (Madam Gong), Park Bu-keon (Director Park), Yeo Dae-hyun (Detective)

Bae Soo-bin (Baek Seon-gyu), Kim Yi-kyeong (Sim Sung-hee), Ryu Kyeong-hwan (Im Hui-guk), Hong Jong-hyun (Moon Do-hyeok), Son Kang-gook (An Do-gang), Kim Yu-mi (Hwang Ji-seon), Kim Min-song (Tattoo Man), Kim Nam-hee (Documentary Host), Go Seo-hee (Madam Gong), Park Bu-keon (Director Park)

Kang Ian (Art Teacher), Kim Yi-kyeong (Sim Sung-hee), Hong Jong-hyun (Moon Do-hyeok), Lee Woong-jae (Heo In-mo), Son Kang-gook (An Do-gang), Kim Yu-mi (Hwang Ji-seon), Kim Min-song (Tattoo Man), Kim Nam-hee (Documentary Host), Park Seung-wan (Jo Yoo-sik)