Upon release, If… received a positive reception from critics and fans, and inspired multiple tie-in print adaptations and a mobile prequel.

As the protagonist, the player explores both the demon-infested Karukozaka High School and five towers based on the Seven Deadly Sins.

During the course of the game, using a wrist-mounted device called a COMP, the player fights demons through a turn-based battle system, using physical and magical attacks to deal damage, as well as healing party members and casting status buffs and ailments on enemies.

[2][3] At Karukozaka High School, bullied and brilliant student Ideo Hazama attempts to summon a demon from the Expanse to exact revenge on his tormentors.

The protagonist is among those trapped in the school, along with fellow students Reiko Akanezawa, Yumi Shirakawa, Shinji "Charlie" Kuroi and Akira Miyamoto.

Should the protagonist side with Yumi or Shinji, they navigate the demon-infested school and towers, finally confronting and killing Hazama.

If the Protagonist allied with Reiko, they enter the Demon Emperor's mind after he is first defeated, and see Hazama's motivations for his actions.

Reiko, Hazama's sister, calms him and stays with him in the Expanse while the protagonist is teleported back to the human world and the school is returned to normal.

[4] The main concept was for a high school setting rendered in three dimensions where a portal to hell would open, creating a more self-contained adventure.

[8] If… was designed to represent the series' titular theme of reincarnation, which had been markedly absent from previous Shin Megami Tensei titles, along with enabling players to continue enjoying the game even after their party was defeated.

The names for Yumi, Reiko and Shinji were inspired by pitchers in the Japanese baseball team Nippon-Ham Fighters.

The PlayStation port contains additional elements such as an easy mode, along with retouched graphics and updated character art.

[19] Hazama's Chapter was intended for inclusion as part of the original release of If…, but space limitations forced it to be cut.

[6][20] An English fan translation of the Super Famicom version was released on October 25, 2018 by the Aeon Genesis team.

The reviewers, while enjoying the music and story, found the graphics dated and felt that players new to the series would find playing through the game difficult.

[7][30] Karukozaka High School was later featured as the setting for an optional story quest in the PlayStation Portable remake of Persona 2: Innocent Sin.