Saint

Saints (聖人) is a term used by Humans to refer to those among them who have "evolved the correct way" and become spiritual lifeforms. The exact criteria for being considered one seem to be arbitrarily decided, but isn't incorrect to call any Human or Demi-Human who has become a spiritual lifeform as a "Saint".

Awakening
The typical process of becoming a Saint involves an Enlightened who has pushed their mind and body to the absolute limit breaking completely through the mental barrier and becoming a spiritual lifeform. This isn't something that can acquired via training for most individuals, instead requiring immense life and death situations to push them past their limit to achieve.

Properties
The immense energy and strength possessed by Saints, in combination with their nature as spiritual lifeforms, gives them the potential to stand on even footing with True Demon Lords and True Heroes as well as a soul strong enough to potentially host an Ultimate Skill.

Incomplete Saints
Incomplete Saints are those who have awakened and become spiritual lifeforms, but whose flesh has not yet ascended to the same status. Incomplete Saints, while possessing greatly boosted energy and abilities, can still said to only be Enlightened physically and possess the weaknesses inherent to the human race such as needing oxygen. The time needed for a Saint to complete this process varies depending on the techniques and talent of the individual, ranging from hundreds of years to mere moments like in the case of Yuuki Kagurazaka. An Incomplete Saint can temporarily surpass their limits and gain the status of a complete saint if empowered in certain ways, such as by God-Grade or Near-God-Grade Equipment, via special skills like Magic Flame Transformation and Divine Berserker, or by Unifying with an Elemental Lord.

Complete Saints
Complete Saints are those whose body has matched their mental awakening and become almost entirely spiritual in composition. They're freed from human limitations such as needing air or food and they have complete and total control over their body and its functions, able to stop their bleeding and close injuries through sheer willpower. Despite their body being "complete" it has not yet transcended the material entirely and still bears a mortal lifespan, albeit an extremely lengthy one. Only the most powerful among Saints have the potential to go beyond the flesh entirely and become Divine Humans.