Ranked 1st as the 'Role Model' by female students and 1st as the 'Girl They Want to Train' by male students! The beautiful star instructor Stella, who appears on real-time search trends more often than most celebrities! The industry is buzzing about her re-contracting, as she boasts the highest value in the entrance exam English field in South Korea. However, instead of choosing one of the many giant educational companies, Stella heads to a newly emerging company, 'LilyEdu', which has just begun to take off! Amidst various speculations about her true intentions, known as the 'Sexy Demon', Taeyeon, who was working in a small lab at 'LilyEdu', suddenly receives a call from the heavenly director?!