A young boy with telekinectic powers and a Gate Holder, holding the Jack Gate. He and his parents were part of a bomb disposal squad, and was taken in by Cartia who just wanted to use him for his powers. He was first ordered by Cartia to reprogram Linda to challenge Rio to a Gate Battle, but relinquishes control of her after Rio won. He later appears in person to challenge Rio to a Gate Battle involving a game of Space Pinball, being offered a chance at freedom if he wins, and initially had the upper hand with his abilites, but is overwhelmed when holographic sharks appeared. He soon lost to Rio after the third stage of the match, but later teams up with her to save Mint from the fourth stage after Linda's head was accidentally knocked off by Carlos. It is hinted that Mint may have feelings for Jack when she persuades him to not use his powers against Rio prior to the match. Jack may also have feelings for Mint as well since it was hinted he was expecting a kiss from her, only to find out after it was from her stuffed bear.
Source: Wikipedia