Cha Eun-woo / ASTRO. A senior in Chemical Engineering at university, an unrivaled "brainy" heartthrob. Possessing sculpted looks and fair skin that instantly captivate countless women's hearts. He is a cold and aloof "Ice Prince" who flatly rejects women who confess their feelings for him. However, to only one person—Roha—he is endlessly warm, affectionate, and sweet; a devoted protector and Roha-obsessed man.
Aroha / 1st year Chemical Engineering student at Astro University. The goddess of Astro University who has captured the hearts of countless men. A devoted admirer of Eunwoo who fell in love with him at first sight.
Hwang Yun-cheol / ASTRO, a senior in the Chemical Engineering department. Jealous of Eun-woo, he falls in love with Roha the moment he first sees her, and is a playboy who falls in love easily while bullying his juniors in the same department.
Eunbyeol / A freshman in the Chemical Engineering department at ASTRO University. She is Roha's best friend with a cute appearance and has a crush on Eunwoo, but she is a loyal warrior who boldly gave up her love for her friend.
Na Yeo-ju / ASTRO, 4th year university student. Yuncheol's girlfriend.
