Also known as: UnnamedMemory, Unnamed_Memory, アンメモ, アンネームドメモリー
A fantasy, romance web novel written by Furumiya Kuji (古宮九時 X Account) and illustrated by Chibi (Shimon) in the light novel adaption.
There's also a manga adaption drawn by Koshimizu Naoki, and an anime adaption that aired 2024-2025.