The characters take on abilities of the classes rather than be of those classes like the Fire Emblem games. It has a turn-based system with a timeline. The game is set in a modern day Japan (unlike the Fire Emblem games). When it is night time the monsters will come out.
The setting, much like most entries in the Shin Megami Tensei franchise, is modern-day Japan, specifically Tokyo. The plot revolves around Fortuna Entertainment, a talent agency that has scouted the main characters.
The main character, Itsuki Aoi, is a normal high school student along with his lifelong friend Tsubasa Oribe and classmate Touma Akagi. One day the three of them come into contact with what are known as Mirages, beings from another world who are drawn to those with creative potential such as Tsubasa (who wants to be a singer) and Touma (an aspiring action actor).
While many Mirages are malevolent and feed of the energy of others, Itsuki and his friends manage to partner with their Mirages and use them in battle (similar to the titular Personas of the Shin Megami Tensei sub-series). Together, they join forces to fight evil Mirages and found out he mysteries of their amnesiac Mirages, such as Chrom and Caeda.
Itsuki Aoi - The main character, Itsuki is a simple high school student who one day comes upon the powers of the Mirages. Unlike the other characters he was practically dragged into joining Fortuna Entertainment and has little interest in show biz.
Tsubasa Oribe - Itsuki's old friend, a clumsy but friendly and perky girl who idolizes her senior, Kiria, and dreams of one day being a singer.
Touma Akagi - A classmate of Itsuki. Passionate and fiery, he wants to become an actor and star in the popular action show MasqueRaider.
Kiria Kurono - An upperclassmen of Itsuki, Kiria is a famous pop singer and has been a Mirage Master for some time.
Eleanora Yumizuru - A half-Scandinavian girl, Eleanora (or "Ellie" as she is often called) is a very successful dramatic actress hoping to break into Hollywood films. Despite being younger than Itsuki and Tsubasa, she is their senior within the talent agency and often treats them as younger than she is.
Maiko Shimazaki - The president of Fortuna Entertainment who gathers Mirage Masters. She is a former model and a lover of alcohol, but also has a very gentle, motherly side.
Tiki - The mascot for a song editing software called Singaloid TiKi that is very popular among young people. Despite supposedly being a fictional character in the setting, Tiki is very much real.
During early production, what type of game it would be became crucial to whether Atlus or Fire Emblem developer Intelligent Systems would develop it. The decision was eventually made to create something along the lines of a traditional RPG, so Atlus took on primary development. Their first concept ended up as a grid-based strategy game with strategic positioning elements similar to Fire Emblem, but they were told by Yamagami and staff from Intelligent Systems to keep within their own skillset rather than trying anything different.
The final product was visualized as a game only Atlus could make, incorporating elements from both series while standing as an original title that could be enjoyed by fans of both Shin Megami Tensei and Fire Emblem. Despite its ultimate form, some of the conceptual ideas were taken from early plans for Fire Emblem Awakening to take place in a modern-day setting.