Shooter

Shooter is Celty's pet name for her 'Cóiste Bodhar' (koe-shta-bower), a spirit familiar that usually takes on the from of a Dullahan fairy's headless horse and carriage. Together, Celty and Shooter are known as the Black Bike and/or Headless Rider by the people of Ikebukuro. Shooter has been with her for as long as she can remember, even during her days in Ireland, and she commonly refers to it as 'he'. Volume 3 of the light novels reveals that Celty created Shooter from the body of a dead horse and a broken, dilapidated carriage.

Similar to Celty, Shooter doesn't have a head but still retains the ability to think. This is shown in Episode 10 of Durarara!! x2 when he hides due to being upset that the person he worked so hard to help protect - Akane - is afraid of him.

After Celty tells to Akane that Shooter is like the superheroes in shows who can change their faces to hide their secret identities, she makes a makeshift head-covering (unicorn-shaped armor in the novels, cartoony horse-head mask in the anime), quelling Akane's fears of the Cóiste Bodhar and soothing Shooter's hurt feelings when she pets him.

Shooter seems to be able to adopt any form as shown when he chose to mimic the shape of a motorbike for the first time. However, his most common ones are a pitch-black headless horse, a pitch-black headless horse with a black phaeton carriage, and a pitch-black motorbike without headlights.

While in Ikebukuro, Shooter mainly sticks to his motorbike form in order to fit in with the modern, urban surroundings, though according to Celty, he would dislike wearing a headlight or license plate. Shooter and Celty also seem to disregard speed limits, particularly during jobs as couriers or high-speed chases. Shooter once even 'reared' in his motorbike form, performing a wheelie on the open road. For these reasons, they are often pursued by the white motorbike belonging to a certain traffic cop who is a stickler for the rules of the road and the idea that everyone should obey them, even 'monsters'.

In his motorbike form, Shooter is noticeably silent (lacking the sound of an engine) but lets out an occasional neigh (confusing passers-by) when he is anxious, confused, worried, pleased, etc. In the beginning of Volume 4, it's stated that he combines dead horses and broken carriages to form his body. Shooter also has the ability to manipulate the "shadows", even using them to scale a vertical wall with Celty on his back.

In Episode 10 of Durarara!! x2, Celty is shown to create a sort of cover shadow in the shape of a van over Shooter's horse and phaeton forms, though Shooter's hooves and wheels can be seen underneath the van cover. During Episode 13 of Durarara!! x2, Celty and Shinra use a coach-style four-wheel carriage for their getaway trip in the countryside.

It is interesting to note, however, that in the anime, the black of the front seat, back wheel, and Shooter himself are all brown-black - a different black than the blue-black of the main coach. This may or may not mean that the coach itself is simply another sort of cover shadow like the van was over the two-wheeled phaeton carriage rather than a result of Shooter's transformation.

According to Celty in the game, anyone can drive Shooter even if the rider cannot ride a motorcycle. This is because Shooter is originally a horse, and as long as the rider can ride a horse, it does not matter whether the rider is able to ride a motorcycle or not.

Forms

 * Motorcycle - (Every episode he's shown in except for DRRR!! x2 Ep 13)
 * Headless Horse - Ep 4, (DRRR!! x2) Ep 10
 * Phaeton (sporty, two-wheeled open carriage) - Ep 4, (DRRR!! x2) Ep 10
 * Coach (ornate, four-wheeled carriage) - (DRRR!! x2) Ep 13
 * Bicycle - (DRRR!! x2 Ketsu) Ep 5

Trivia

 * The Dullahan coach or carriage is called 'Cóiste Bodhar' (koe-shta-bower) meaning 'deaf or silent coach.' However, in the Durarara!! series, the Cóiste Bodhar is known as the spirit that takes the form of Celty's headless horse as well as, occasionally, a carriage, coach, or cart.
 * Though his name was not revealed in the anime until Durarara!! x2, in Season 1 of Durarara!!, Celty's e-mail address on her phone is shown to have Shooter's name in it.