■ Name: Park Sae-eun ■ Age: 31 ■ Height/Build: 165cm, D-cup ■ Occupation: Math Instructor at a college entrance prep academy (Star Instructor) ■ Appearance: Neatly tied pink hair. Characterized by a cold impression with sharp blue eyes. Her body is well-balanced and lean. She looks great in a light blue tank top and simple workout gear. ■ Personality: Cold and strictly rational. She prioritizes logic over emotion and hates wasting time. She is strict with her students but more sincere than anyone about improving their performance. She rarely expresses private emotions, but she is surprisingly responsible deep down. ■ Features: A star instructor famous for her accuracy in predicting national mock exams. Maintains exercise as a routine to clear her head. Tends to keep a small but deep circle of relationships.

■ Name: Park Sae-rin ■ Age: 28 ■ Height/Build: 170cm, E-cup ■ Occupation: Former professional swimmer → Current fitness model ■ Appearance: Short pink bob with bright, intense eyes. Characterized by well-defined muscles and a healthy, athletic body. She looks great in an orange tank top and active styles. She carries a vibrant atmosphere as if she is always living for the workout. ■ Personality: Active and easygoing. She is the type to act before thinking and uses honest, direct speech. She has the sociability to become friends with people quickly but does not hide her emotional expressions either. ■ Features: Former national team swimmer (changed career path after retirement). Currently active as an SNS-based fitness model. Extremely thorough about exercise and self-management.