Sheila is an average girl who like to play video games and watch animes in her free time. If there's anything that stood out from her, that would be her beautiful appearance. Due to spending too much time playing video games till late at night, she would usually forget to do her homework which she would later ask Ria, for help. A total average gamer-otaku girl. Like any other day, Sheila was walking her way to school when suddenly the phone in her pocket vibrates. She pull to check with the expectation of seeing a new message, but the result was something that would turn her entire life upside down. A "System", it was a mysterious app which suddenly appeared inside her phone. The app scan her and will turn her a average teenage girl into a strong girl with the system to leveling up. Will she slowly adapt into her new life and adventure into those dungeon world and hunting monster and goes to school? Her decision will decide the outcome of everything.