Ceremonial Magic: Linked to ceremonial magic, which is a form of ritual magic that follows specific ceremonial procedures and often involves the invocation of entities or spiritual forces.

Symbolism of the Triangle: The triangle in ceremonial magic is a symbolic space used for the manifestation or confinement of entities. It serves as a protective boundary during magical operations.

Concretization and Manifestation: The mention of "concretization" and "manifestation" indicates that the use of the triangle is intended to make non-required entities manifest in a controlled manner.

Protective Circle: The reference to the protective circle suggests that the triangle is placed outside of this circle to safely contain and control any entities that may be summoned.