Pneuma Core

Pneuma Core (魂魄心 Konpaku Kokoro or alternatively ニューマコア Nyūma Koa) is where the life essense of any being, either a being made out of flesh or a wholly spiritual being, is stored. These usually appear as ovoid or oblong gemstone-like entities, but in fact the oblong part AREN'T where the life essense is stored, but in fact they are stored inside a smaller, heart-shaped component located in the center of the oblong-shaped "body". These play a major part in the story and gameplay of Claire: Chronicles of the Carmine Blood.

Gameplay
Similar to Undertale, the player, during battles against enemies, must move the protagonist's Pneuma Core in order to dodge the enemy (ies)'s attacks. If the player failed to so, their HP will be reduced to zero, and results in a Game Over.

Pneuma Cores of beings made of flesh
Pneuma Cores of beings made of flesh are bigger in size and have bigger heart-shaped central components, and are more vulnerable to physical attacks than that of the wholly spiritual beings. There are also differences between the Pneuma Cores of that of earthly humanoid beings and "beasts": A humanoid's Pneuma Core will continue existing even after the body's death; while that a beast's Pneuma Core disintegrates after death, in a manner that resembles monsters from Undertale.

Pneuma Cores of wholly spiritual beings
Pneuma Cores of wholly spiritual beings, as contrast to that of beings who are made of flesh, are having a smaller size (both the oblong-shaped "body" and the central heart-shaped component), are invulnerable to physical attacks, but can be damaged by "impurity" of sins, darkness and fear. However, since the body that houses these Pneuma Cores does not die, when they are severely damaged, they cannot be completely destroyed, but reverts to a "sleeping state" that they allow the purification of sins by God to purify them and restore themselves fully. The colors of these Pneuma Cores are generally pastel colors, in contrast of that of beings made of flesh, whose have Pneuma Cores which are colored in vivid colors.

Trivia
The concept of the Pneuma Cores are influenced by that of the SOULs from Undertale.