In his most common form, Elias is a bipedal humanoid with the skull of a wolf and horns of a goat in place of a head, with glowing red beams of light in the empty sockets of his eyes. Chise mentions that his eyes change depending on his emotions. He is much taller than the typical human, with the average person only reaching his chest. His neck is the only part that shows skin, of which is a dark purple in color. He wears a three-piece suit: a black robe with sleeves embroidered with white threads, paired with a black vest (blue in the manga) and white undershirt. He also sports a bluestone bolo necktie tucked just beneath his collar (it was gifted to him by the one who gave him his name). His horns are adorned with a string of gold that hangs to his neck and connects to a red cloth. When outside, he will often pull the red cloth behind his head over his face. However, with magic he is able to change his appearance to that of a human of his choice, usually with two tufts of hair that spiral into a horn-like shape. His true form takes on an appearance akin to that of a beast. He's taller, though thinner, taking on a collar of black feathers. He gains a tail and claws. A tattered black cloak appears to drape against his back, though it seems to be a part of his body. Thin thorns twist in every direction, an additional pair of horns curve toward his face, and a series of rib bones curl around his chest to form an extra ribcage.
Though polite and kind, Elias is noted to be immensely reclusive because of his inability to relate to humans and rarely interacts with others as a result. Elias is extremely fascinated by humans and their emotions, which he attributes to being unable to experience them himself. To this end, he has adopted the mannerisms of a classic "gentleman" and closely studies people, though is usually unable to imitate their examples. Though withdrawn, he has a tendency to be aloof and has an unfriendly streak with certain people. He says he does not lie but keeps his intentions shrouded by leaving out information and goes through the effort of keeping his past hidden. But despite a few instances of malice, he has a number of child-like tendencies, including throwing tantrums. Despite this, he is very willing to amend his wrongdoings, and while his exact actions are in explicit he regularly does deeds for the church as recompense.
Initially, Elias is underdeveloped emotionally. He understands emotions through one-sided observations as if only knowing them by definition and never experiencing them himself. He describes his emotions in a physical sense, like the twisting in his chest, and the cold of Chise's absence. Despite his usual calm and stoicism, endangerment to Chise's well-being is enough to send him into a rage and seems to be the only thing capable of such.
His inexperience with his emotions later drive some of his actions, such as holding Chise against her will and attempting to use Stella as a sacrifice, despite knowing it would make Chise sad after he unknowingly developed romantic feelings towards her.
The only memories from his past are the color red and the recollection of eating humans. His first memory is waking in a forest. He had decided to walk, wandering in the snow and avoiding humans until he collapsed in front of Lindel. Lindel takes him to his master, Rahab, who decides to give him his current name, and persuades Lindel to take him on as a magic apprentice. From there, he begins learning magic from Lindel while living a nomad life caring for caribou. An unknown gap of time between these events, Lindel and Elias separate, and Elias finds himself in Britain doing various odd jobs for the church.
Elias appears to purchase Chise in the auction, introducing himself to her and bringing her to his home to explain the nature of her apprenticeship. Later that evening, he spots Chise leaving and follows her within her shadow to avoid having her taken into the land of the Fae by the Aerials and returns her to his home to rest for two days.
After that, he introduces Chise to Angelica, who hits him after learning he bought her, and has to stop her from using her magic to make crystal poppies. Once they arrive back home they find Simon waiting for them and they're given three assignments to handle for the Church. Elias decides to head off one of them and it brings them to Iceland.
There they run into a dragon that spirits Chise away while Elias hides in her shadow, bringing her to Lindel. The two are introduced as being old acquaintances for the last 300 years at least, where they discuss Nevin's passing and that Chise will have a short lifespan if something isn't done soon.
Their next tasks takes them to Ulthar, where the King of Cats request that they deal with a blight resting in the lake. Elias goes off to investigate magical residue he's been sensing until Chise is dropped into the water by Alice and he pulls her out, before returning that night to try and purify the blight. Alice and Renfred formally appear, wanting to claim it for themselves, but once Chise scatters it and guides the souls within it to their final rest, both parties depart from Ulthar. The effort again exhausts Chise, but Oberon, Spriggan, and Titania appear to help her recover shortly afterwards.
Their final task is to investigate a series of murders at a local Church, thought to be caused by a Church Grim. Elias goes off to investigate once more, only to return after Chise has captured Alice. Once they learn that Joseph is involved in the case and he harms Chise, Elias turns into his monstrous form in front of her for the first time in an attempt to kill him until Renfred shoots Joseph in the back of the head. He settles down afterwards and has to keep Chise from using her magic recklessly until she forges a contract with Ruth and they send Joseph off.
The act of changing his form takes a toll of Elias, leaving him having trouble for a few days afterwards in stabilizing it until Chise seeks him out and confesses she wants to know more about him when Lindel's familiar appears to tell him that Chise has to go pick up her wand alone. Left waiting for her return, Elias copes with the feeling of loneliness for the first time when he receives a messenger bird from Renfred telling Elias to let Chise know about the College, but he destroys it and has Silky bury the remains in the garden.
After that, Chise contacts him through the water mirror and then flies back to his side, whereupon she wakes up later again due to using magic recklessly in time to shear Woolybug. Chise is attacked and he takes her into the greenhouse to recover, but learns that she recalls him nearly eating her before she left with Lindel, so he attempts to remove her memories of it. He only relents when she admits that she's fine with keeping the memory before admitting he has trouble empathizing with humans due to his nature and asks Chise to teach him how to do so.
Later on, Chise finds herself near-death due to exhausting her magic creating Fairy Ointment and Elias has to take her into the Land of the Fae to recover. There he has an audience with Titania where he rejects her offer to reside in that world along with Chise before returning home several months later and assisting Stella with recovering her brother from Ashen Eyes.
In a tragic turn of events after this, Lindel has two of his dragon whelps stolen by Joseph and in the attempt to reclaim them Chise takes on a Dragon's Curse. Mariel advises Elias that the curse could be moved from one host to another, and he seeks out Stella to do so because a feeling of jealousy. This drives Chise to go with Joseph when he has her hostage and he ends up nearly accepting Titania's offer once more in exchange for finding her, only to reject it and realize that he can't keep acting that way. However, Titania extends her hand freely to help him find Chise along with several others and they give chase after Joseph.
The battle largely plays out like in the anime, and afterwards Elias exchanges rings with Chise before the two of them become members of the College, with Elias taking the role of a professor due to his knowledge. His first class has him call upon the Neighbors within the College to assist the students, but he's forced to drop his glamour in order to prevent one who overstepped their bounds from getting hurt.
Elias works with Aerial to defeat Ashen Eyes before taking Chise home once more where they discuss their issues and come to a compromise. The anime ends with the two of them then exchanging rings in an informal wedding before returning home.
Skills and Abilities
Elias Ainsworth is a magician whose skills specialize in shadow and magic that has a destructive leaning. He can hide in the shadows of other beings such as Chise, and can also produce thorns, earning him the names "Child of Thorn" (or just Thorn) and "Pilum Murialis". He's also capable of removing memories.
He is also able to shapeshift, usually taking the appearances of people he has known.
"Nettles in the shadows, a wheel of hollies. Ten-folds and twenty-folds, weaves the spider's thread of the nest to the branch"- Elias uses this incantation to teleport him and a recently purchased Chise directly to his home in England. Thereafter, he seems to use different variations or only parts of the chant to do other magic. Such as his spell for drying chise after she is dropped in the lake in the nest of dragons.
- He often says "die" to people who anger him more than not.
- Because of his horns, he can only sleep sitting up or laying on his chest.
- Elias is probably a Wendigo (also spelled Windigo), a formerly human malevolent spirit who has engaged in cannibalism. The creature originates from Native American folklore.
- In Official Guidebook: Merkmal, his height is 200cm (6'7").
- Elias wears black leather Classic Oxford Shoes, a common English shoe worn by many businessmen. Oxford is also close to the undisclosed location where Elias lives (it is likely to be within the Cotswolds).
- The tea he serves Simon is an iced variant of Elderberry tea, a tea brewed using the dried berries of the Elder. Elderberries are toxic until dried or cooked; the tea is ideal during the winter as it staves off colds. Elderberries are collected during September and October in England.
- Elias' first name is pronounced like the Scandinavian "Elias" by Kore Yamazake as well as most of the characters in the show. Furthermore, Elias was named shortly after Russia, Norway, and Sweden were mentioned, so his story likely begins in that area. (His name could also be English and mispronounced, due to the poor transcription of "Elias" in Japanese: エリアス.)