Cogsworth is a character first seen in Kingdom Hearts II, that returns in Kingdom Hearts 358/2 Days. He is actually a servant of the Beast who was enchanted by a spell along with all the other inhabitants of the castle. The spell turned him into a clock whose hands give him a mustache. He is often paired with the other castle staff members.
Cogsworth naturally has a serious demeanor which is evident in his strict attitude in serving the Beast and ordering the other servants around constantly. However, Cogsworth does mean well and is as good-natured as Lumiere is. He is Lumiere's best friend and also a rival of sorts.
Cogsworth's preference to abide by the Beast's rules often puts a severe strain on his friendship with Lumiere, who opts for a more rebellious and care-free personality, but overall, he values his friendship with Lumiere and sees him as a brother, demonstrated in the original film (when he saves Lumiere from being melted by LeFou, Gaston's henchman) and the midquels.
Under the influence of the curse, Cogsworth takes the form of a mostly brown clock with a peach-colored clock face that is literally his face. He has straight, white teeth, close-set, green eyes, brown eyebrows, and a yellow "nose" that is actually a flat button that connects to the clock hands, which act as his "mustache". The hands are both brown and end in a heart-shaped point. The minute hand points to the diagonal lower-right and has a hollow point, with only the outline of the heart present.
The hour hand points to the diagonal lower-left and has a solid point, as well as two small circles on the middle of the hand. He also has two small, brown triangles on his face, one on either side. There is a curly, brown and yellow woodcut design on the top of his head that vaguely resembles hair. Cogsworth's body is rectangular and sports a case containing a circular, gold pendulum inside it, visible through a glass window on his chest. A gold design just under his head resembles an ascot. His "arms" are actually the yellow, curled handles on the sides of the clock, and the four, short legs of the clock act as his feet. He walks by moving two of the legs at once.
On the first visit to Beast's Castle, Belle tells Sora to rescue Cogsworth and company from the castle dungeon. Upon doing so, he tells Sora about the Beast's curse and how they were imprisoned by the Beast. Then he and the others show Sora a secret passageway to the West Wing and the Beast's room - Cogsworth's job is to lower the lamps for Sora and company to light them.
Cogsworth also moves the knights blocking the entrances to help movement for Sora and the others. When Sora, Donald, and Goofy fight the Beast to turn him back to normal, Cogsworth assists by making loud noises to wake the Beast up, with help from Sora's Keyblade.
In the credits, the Beast was turned back to Prince Adam, implying that Cogsworth returned to his normal form as well.
Cogsworth is originally from the movie Beauty and the Beast. He was the Beast's majordomo (butler/head of the household under the master) before he was cursed alongside all the other workers. He was changed into a clock because of his strict personality, keeping on time just as well as a clock.