Will Heim is one of the 6 Stigmas that appear throughout the series. Often referred to as "The Eyes of Envy" due to it causing its bearer to see themselves as inferior to others as jealousy sets in, causing its bearer to become more hateful of others around them. They have higher tolerance to others who also bear cursed eyes. This stigma, along with the Lino Doue can hear what Tiir refers to as "God's Voice". There is no known bearers of this stigma.
- Analyzation Will Heim possesses an analyzation ability that lets them see every strength and weakness of whomever they are looking at.
- Extraction Like any other typical stigma, if a bearer of Will Heim has their Stigma forcefully taken and crystallized will be killed automatically, as a stigma to its bearer is a vital organ like the brain and heart.
- Inferiority Complex Due to the ability to see a person's strengths, they often get jealous of these strengths, and will become hateful and likely easily mad at people.
Due to it having little to no spotlight, the abilities of a crystallized Will Heim are unknown.