Cuphead is the titular main protagonist of Cuphead. He is Mugman's brother and, like the rest of his family, lives on Inkwell Isle. He is usually played by the first player and, as a result, was the default character for Player One before the update in April 2019, after which the first player can choose whether to play as him or Mugman.
As his name suggests, Cuphead's head is a wide cup with what seems to be some sort of liquid inside, topped with a red and white striped straw. His face consists of eyes that are very close together with black pie-cut pupils, and a small red nose. He always has a determined expression in the face of danger.
He is mostly seen wearing a black, long-sleeve shirt, white gloves, red shorts (slightly similar to Mickey Mouse's iconic short overalls), and brown boots. To emulate the way characters were drawn in the game’s time period, his coloring is inconsistent; he is sometimes depicted wearing red or yellow boots, and/or yellow gloves instead. As an anthropomorphic cup, his skin is a light gray and made of porcelain, so enough hits could break and kill him, leaving behind his apparition.
His ghost still has the cup head and gloves, but his appearance is now a ghostly blue. His shorts and legs are now replaced with a ghost tail, his straw is now a halo, and his expression is that of melancholy. In the center of Cuphead's ghost's chest, there is a pink heart which can be parried to resurrect him. When used as a Super Art, his ghost is muscular and his expression is determined.
If the answer "Yes" is chosen in the cut scene with the Devil before his battle—triggering the bad ending—his appearance dramatically changes. He is now seen with purple shorts, a broken purple straw, a purple nose, evil-looking yellow eyes with black and red pupils, a maniacal smile, and sharp teeth. In some artwork, he is also shown to have fire rising out of his head.
In The Cuphead Show!, Cuphead's appearance is the same, with a few differences. His colors are a little more duller, his gloves are yellow all the time, and his skin has a tannish tint to it.
Overall, Cuphead's appearance is reminiscent of character designs from classical 1930s cartoons, of which the game's art style is designed around.
Cuphead is relentlessly optimistic, his confidence and drive for adventure can lead him to appear devious, or get him into trouble, but at his core, he is kindhearted who wants to do good—but has the tendency to leap before he looks.
Cuphead seems to be a daredevil. He is shown to be the more confident, fun-loving and slightly cheeky type. He (in contrast to his twin brother) often takes quite the amount of risks. His personality was mostly inspired by the "charming, yet trouble-making" character archetype, as seen in the protagonists of early cartoons.
As seen in the introduction, Cuphead seems to have a somewhat greedy personality, apparently willing to risk anything to get what he wants, causing the infamous bet which nearly cost the souls of him and his brother. Despite his flaws, however, he seems to be kindhearted and has good intentions overall, such as in the good ending where he and Mugman burn all the soul contracts, setting everyone free.
In The Cuphead Show!, Cuphead's personality remains the same, but is shown to be a little more reckless, and often gets into fights with Mugman.
In Inkwell Isle, Cuphead and his younger brother, Mugman, lived happy and carefree under the watch of the Elder Kettle. One day, the boys wandered far from home and ended up in the Devil's Casino, despite the Elder Kettle's warnings.
In the casino, Cuphead and Mugman were on a winning streak at the Craps table. When the Devil came to the table, (which was a surprise for the boys) he offered a bet: if the boys won, they would get all the loot in the casino, but if they lost, the Devil would take their souls.
Cuphead, blinded by easy riches, rolled the dice and landed on snake eyes, losing the bet. Cuphead and Mugman begged for their lives, and so the Devil sent them on a mission to collect his debtors' soul contracts by midnight, saying he would consider sparing them. Cuphead and Mugman ran back home as fast as they could in a panic to the Elder Kettle, who gave them a potion granting powerful abilities to aid them on their journey.
After some training, Cuphead and Mugman went to go to collect the soul contracts, using their powers to battle bosses, run through levels, and save the Legendary Chalice. When travelling from Inkwell Isle One to Inkwell Isle Two, the Elder Kettle informs the boys that their strength is growing thanks to the power of the soul contracts, and soon it will be enough to defeat King Dice and even the Devil in battle.
Once all of the soul contracts are collected, the boys meet up with King Dice, who forces them to play a "game" before they can see the Devil. After King Dice is defeated, Cuphead and Mugman meet up with the Devil, who was awaiting them in his office. What the pair does depends on the choice that the players decide. If the players decide to give the Devil the soul contracts, Cuphead and Mugman become his personal lackeys and are turned into demonic cups, resulting in the "bad" ending. If the players decide to not give them the soul contracts, the Devil will become outraged and battle them.
Upon the Devil's defeat, the boys accept his surrender and burn all of the soul contracts, releasing the residents from their eternal servitude to the Devil. The boys then went home and told the residents that they are now free from their debt. They are praised for their bravery, and an all-day celebration began. In their success, the boys promised to never get into trouble again—until the next time.
Finger Bullets - Cuphead can create energy bullets by constantly snapping his fingers. He can also charge them up to preform an EX attack, which is usually a much larger bullet that hits multiple times. The type of bullets depend on what potion you buy:
- Peashooter - Cuphead’s primary weapon, light blue, long bullets that travel non-stop with long-range and average damage.
- EX Move: Mega Blast - A huge fireball that hits multiple times,
- Spread - Shoots red pyramid bullets the spread in 4 rows. It has a limited range.
- EX Move: Eight Way - Sends 8 large bullets all around Cuphead.
- Chaser - Shoots green homing bullets. Has below-average damage.
- EX Move: Chaos Orbit - Sends multiple homing bullets that attack. More bullets orbit Cuphead and damages enemies that touch him.
- Lobber - Purple orbs that bounce twice before popping. Does a lot of damage but has delayed shooting.
- EX Move: Kablooey - A large orb that explodes on impact.
- Charge - An orange fiery horizontal spiral that can be charged to deal a massive amount of damage. Takes a long time to charge.
- EX Move: Radical Barrage - A large explosion that affects all around Cuphead.
- Roundabout - A light blue boomerang-like bullet that will come back if it didn't hit something after a short distance.
- EX Move: Jumbo Rebound - Sends a large boomerang bullet that hits multiple times.
Dashing - Cuphead can dash a short distance in both mid-air and on the ground. With the Smoke Bomb ability, he can "teleport" while dashing and not take any damage.
Parry Slap - While in mid-air or flying his plane, Cuphead can attack pink objects by turning his straw into a hand and slapping it, whether it be enemies, projectiles, or objects. Parry Sugar will allow Cuphead to automatically parry whatever he jumps towards. This helps fill up the Super Meter, needed to perform a Super Art.
Resurrection - When Cuphead dies, he can be resurrected when his heart, which is in the center of his soul, is parried. As long as Mugman is with him and his soul is still on screen, he can return to fight.
Flight - While Cuphead cannot exactly fly himself, he is a master pilot and comes equipped with his own red fighter plane, complete with bullets
- Rapid Fire Bullets - The default bullets for the plane. Like the Peashooter bullets, Cuphead can shoot multiple bullets and they have a long range.
- EX Move: Toothy Terror Missile - Simply known as "Attack," Cuphead shoots a missile with a Toothy Terror mouth that does multiple damage.
- Mini Bomb - Shoots missles in a downward arc that do above average damage to the enemy but have a slow fire rate.
- EX Move: Magnet - Shoots multiple magnets that home in on the target.
- Size Reduction - In his plane, he can shrink himself to be part of the plane, making it easier to dodge attacks and increases speed. Cuphead can still use his bullets while in this shrunken stage, but they do less damage and have a limited range.
- Super Bomb Transformation - As a Super Art, Cuphead can transform into a giant bomb that explodes either on impact or the if duration timer runs out.
Energy Beam - The energy beam is the first Super Art to unlock. Using the liquid from his head, Cuphead spills it as a horizontal beam that damages enemies.
Invincibility - As the second Super Art, Cuphead crosses the astral plane by transforming into a large, eyeless version of his head that spits out a gold, sparkling, complete version of himself. This makes Cuphead invincible for a few seconds before returning to his normal state.
Giant Ghost - As the final Super Art, Cuphead sends his spirit out of his body. Unlike Cuphead's spirit when he dies, his spirit is now larger and muscular. The direction the ghost goes depends on how Cuphead is moving (i.e if Cuphead moves left, the ghost goes left). The ghost damages any enemies he is near. He does this for approximately 10 seconds before he disappears except for his heart, which goes slowly goes up. His heart can also be parried.
Astral Projection - With the last two Super Arts involve him going into the astral plane, it can be implied that Cuphead has the special ability to enter the astral plane and have out of body experiences.
- Made of porcelain: 3 hits can kill him (4 while equipped with the Heart Charm and 5 while equipped with the Twin Heart Charm).
- Can't be resurrected without the help of Mugman (likewise, Mugman can't be resurrected without Cuphead).
- Easily manipulated, making a very high-risk bet due to being blinded by riches.
- In the beginning moments of a boss battle, Cuphead will hoist his pants, smiling, with determination on his face. The sole exception to this is the fight with The Devil, where he seems to be terrified, using sprites reused from the ones Cuphead uses if he fails to stop The Spectre Syndicate from reaching The Legendary Chalice's urn in the Mausoleum levels. After the update, he may sometimes pump his muscles with a more determined grin.
- According to an interview with Studio MDHR, the liquid inside Cuphead's head is the essence of his soul.
- However, people believe that Mugman drinking himself is evidence that the cups hold milk in their heads.
- Cuphead is based on old cartoon characters, most notably the cup from the cartoon "Omochabako series dai san wa: Ehon senkyûhyakusanjûroku nen (1936)"  as stated by a developer.
- He is also heavily based on Bimbo the Dog.
- He is also likely to be based on Mickey Mouse (except that Mickey Mouse's shorts are overalls and have the waist going up to the chest and having buttons and suspenders sometimes) and Felix the Cat.
- He may likewise have been influenced by the design of various sentient porcelain characters from the 1934 Silly Symphony The China Shop.
- Cuphead's shoes and gloves will change color depending on what screen he is on. In the title screen he is seen with white gloves and brown shoes, in the world map he is seen with white gloves and yellow shoes and in the results screen after defeating a boss he is displayed with yellow gloves and brown shoes. This color inconsistency was deliberately done by the developers as many cartoons in the 1930's had posters where the character's shoe or glove color would be slightly different from the original.
- According to Evan Skolnick, Cuphead is an adolescent. However, in a Twitter response to a fan, the Studio MDHR jokingly described Cuphead as a "kidult".
- In the E3 2015 trailer, Cuphead seems to pour a beverage labeled "XXX" into his head, though he is never seen doing this in the final version.
- Cuphead can remove his head. However, Cuphead is seen swallowing with a neck in "Crisp Apples".
- In Super Smash Bros. Ultimate, Cuphead appears as a Gunner Mii Fighter Costume, along with the Floral Fury from Cagney Carnation as an extra music track. Cuphead also became one of the Spirits for the "Ready? Wallop!" event, along with Mugman, King Dice, and The Devil.