Pump is a very tall humanoid demon. At first sight he can be mistaken for someone wearing a full set of magenta armor, when this is his actual body. He has very large hands which have sharp blade-like fingers.
Pump is very competitive and lonely.
3,000 years ago
The Six Knights of Black were part of the battle against the four races in the Sky Temple, where an Indura brought destruction. When the victory of the Demon Clan seemed certain, the Great Oshiro appeared and defeated the Indura, allowing the Goddess Clan to seal the Six Knights of Black, the Indura and other Demons within the Egg Rock.
After 3,000 years, when the seal of the Egg Rock fall apart, the Six Knights of Black were released from their imprisonment. Pump manage to kill several Celestials in order to use their souls to release the Indura. He is then attacked by Ellatt, and Pump wonders if he must kill her of make her suffer. Meliodas then stops Ellat before she gets pierced by Pump's needles. Understanding that Meliodas is Bellion's objective, he let him to fight Meliodas and gets annoyed by Bellion's ignorance towards his desire of enjoy fighting.
Pump resumes his fight with Ellatt, resisting all of her sword hits and then paralyze her with his Hypno Stinger. However, before he can kill her, Ellatt is saved by Solaad and then Ban appears to fight Pump. Despite being overwhelmed by Ban in the fight, Pump manages to paralyze him and then impale him with his body needles. However, Ban recovers instantly thanks to his immortality and break apart Pump's body with a bear hug.
His soul along with his companions' are later sacrificed to the Indura by Bellion.
Abilities and Equipment
As a member of the Six Knights of Black, Pump is stronger than an average Demon. He can use long needles that come from his body to attack his targets.
- Hypno Stinger「ヒュプノスティンガー Hyupuno Sutingā 」: Pump stings his opponent with a poisoned needle that leaves it paralyzed. 
- Ellatt & Meliodas vs. Pump: Indecisive
- Ellatt & Ban vs. Pump: Lose
- He makes a cameo appearance in the intro on the Demon's side.