Root Letter is a visual novel adventure game developed and published by Kadokawa Games. The player delves into the mystery of Aya's disappearance after receiving a peculiar letter. The gameplay comprises two main parts: an adventure segment where the player interrogates characters linked to Aya to unravel the mystery, and simulation portions where the player experiences past interactions with Aya.

Root Letter presents a compelling narrative where players engage in investigative gameplay to uncover the truth behind Aya's vanishing. With a blend of adventure and simulation elements, the game offers a unique and immersive experience for those intrigued by mystery and visual novel genres.