In an interview with the game's director Takumi Isobe published in Famitsu on February 22, 2024, Isobe explained that the game's title "Reynatis" holds deep significance to the game's story and is derived from two words. The first is "renatus", which means "birth" or "rebirth" in Latin. The second word is "rey" which means "king" in Spanish; additionally, "renatus" on its own can also refer to a "born king" in Spanish.

In an interview with the game's director Takumi Isobe published in Famitsu on February 22, 2024, he mentioned that the Kingdom Hearts and Final Fantasy series significantly impacted his sense of values and influenced the development of Reynatis.