Caerula Memory
The Caerula Memory is a Collectible in Mizuki & Caerula Arbor, added in its Expansion II.
Even vague memories of the lab's research are enough to induce fear. Perhaps you and people like you have all done something unforgivable for the sake of survival.
Effect
One of the cursed Collectibles in Caerula Arbor, the Caerula Memory causes the player to lose 100(!) Light – instantly extinguishing it in the process – and a random Operator to be afflicted with Rejection when obtained.
The player, however, must obtain the Caerula Memory for Encounter: Sublimation and Encounter: Caerula Ritual where 
"Determination"/
"Vigil"/
"Hesitation" and 
Caerula Arbor, may be obtained to appear.
Acquisition
The Caerula Memory is obtained from Encounter: The Beginning with the option that awards it only appears after the player had completed a run from Expansion II.
Since the aforementioned Encounter only appears in the following runs after the player had completed a run with the Age of the Silence ending, it is impossible to obtain the Caerula Memory before then.