Main •
Song Seung-heon as Kim Hae-kyung, a psychiatrist and food psychotherapist. •
Seo Ji-hye as Woo Do-hee, a producer-director at 2N BOX. •
Lee Ji-hoon as Jeong Jae-hyeok, a medical journalist freelancer. Do-hee's first love in college. •
Son Na-eun as Jin No-eul, a fitness instructor. Hae-kyung's first love.
People around Hae Kyung •
Lee Hyun-jin as Kang Gun-woo, stylist. • Kim Seo-kyung as Lee Byeong-jin, Hae-kyung's secretary. • Jeon Guk-hyang as Lee Moon-jung, Hae-kyung's mother.
2N BOX •
Ye Ji-won as Nam Ah-yeong, CEO of 2N BOX and friend of PD Woo Do-hee. •
Ko Kyu-pil as Park Jin-kyoo, planning team leader. • Ahn Tae-hwan as Kim Jung-hwan, planning team member. •
Oh Hye-won as Im So-ra, ASMR creator. •
Kim Young-chul as Jjoda Man.
Do-hee's family •
Jung Eun-pyo as Woo In-ho, Do-hee's father. •
Yoon Bok-in as Jun Sung-ja, Do-hee's mother.
Others •
Park Ho-san as Keanu / Kim Hyun-u
Special appearances •
Kim Jung-hyun as Lee Young-dong, Do-hee's ex-boyfriend (Ep. 1–2) •
Jung Sang-hoon as ER doctor (Ep. 2) •
Kim Hyun-sook as Keun-hee (Ep. 1–2, 8) •
Lee Si-eon as food truck operator (Ep. 3) •
Sandara Park as Hae-kyung's patient (Ep. 11) •
Tae Jin-ah as himself (Ep. 4) •
Kim Won-hae as depressed widower (Ep. 7) • Kim Jae-won •
Seo Eun-soo as flight attendant (Ep. 1–2) • Ryu Ji-kwang as himself (Ep. 14) •
Kim Hee-jung as eating show host (Ep. 14) • ?? as Do-hee's blind date mate (Ep. 28) ==Production==