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Agares wears the typical school uniform, but does not wear a tie and leaves his blazer unbuttoned. His sleeves are either longer than normal or simply too long for his arms, reaching to his knuckles. Under his coat is what seems like a buttoned-up pajama shirt with sleeves reaching farther than his coat. He doesn't wear any shoes, revealing his white socks. He also wears an eye mask with fake eyes which move (much like Clara's slippers) and a sleeping cap. Has a beautiful face under his eye mask. He also has pointy ears, fangs that sometimes stick out, hair that is curly on the ends but usually covered by his cap, and wings.
Walter Park Arc
Following the end of their Final Exams, Agares ended up finding himself dragged to Walter Park with the rest of the Abnormal Class (except for Allocer and presumably Purson), where he is placed in Balam Sicirue's chaperone group with Iruma, Alice, and Sabnock.
Harvest Festival Arc
He was assigned alongside Gaap to Lady Vepar, whose plan is to enhance their bloodline abilities. She emphasizes that their abilities are strong, but only on the ground, so she trains the two to overcome situations where they cannot use their abilities by trapping them underwater. 
My Area: He can manipulate the state of ground types.
Soil and Tree Manipulation: A variation of his Bloodline Magic, Agares can exploit and control soils and woods that reside in the ground (as long as it is attached in the ground itself), then combines all together and turn them in structure that acts as "the top part of his bed"..
Cloud Pillow: Agares is always seen with the fluffy white-colored cloud pillow with a pair of eyes that forms as his bed. Sleep Mask: Having a habitual sleepiness and hating seeing sunlight, Agares often covers his eyes with the green-colored sleep mask. Possibly to try to avoid getting reprimanded for sleeping during classes, the sleep mask has a pair of eyes intact of them that are actually moving, though most of the time they are in a groggy postilion, but it is unknown whether he can see through the mask.
In demonology, Agares (also spelled as Agreas) is a Duke who rules the eastern zone of Hell, having 31 legions of demons under his command. He can make runaways come back and those who stand still run, causing earthquakes from the underground, destroy dignities (both temporal and supernatural), and grand noble titles to others. He is depicted as an old man riding a crocodile, carrying a hawk on his fist.