- "The senses by which you feel and pick up on reiatsu... They're known as "Reikaku", or "Reiatsu Chikaku". Every person that has reiatsu subconsciously uses both their sense of vision and their reikaku at the same time in order to see. And when concentrating in the midst of battle, reikaku takes over an overwhelming amount of perception. In other words, your subconscious begins to stop seeing with your eyes."
- —Shunsui Kyōraku
|Users||Those possessing Reiatsu|
Reikaku (霊覚, "Spiritual Sense"), also referred to as Reiatsu Chikaku (霊圧知覚, "Spiritual Pressure Perception"), are the senses used to detect Reiatsu. It can be considered a sixth sense, in contrast to the five physical senses, which operates at the spiritual level and whose sensory organ is the heart. According to Shunsui Kyōraku, all beings that possess spiritual power undoubtedly possess the ability to perceive the spiritual pressure emitting from them.
Those that have refined their mastery over reikaku are able to determine various aspects regarding the nature of one's spiritual pressure. Reikaku can be used to pick up on intentions, emotions, movements, and even effects that the mind simply cannot, and as such, it becomes the ultimate weapon for Hakuda practitioners against opponents of equal or greater capabilities than themselves. Furthermore, it can even be used to gauge the strength of an opponent that may stand before them, making it possible to appropriately determine how powerful an opponent may possibly be, what degree of strength they could be hiding, and also the amount of force behind any particular form of attack. It can be used to discern how strong a defense might be and how much power is needed to smash through it. Reikaku also allows one's perception to actually measure the intentions of the opponent, even to the point of ascertaining if their hearts are positive or negative; almost as if being able to tell if a person is good or evil, based on their individual perspectives.