A giant bald fat man, Heart's stomach was actually composed of a rubber-like substance which absorbs the impact of most martial art techniques, which earned him the nickname of the Destroyer of Fists. While normally calm and more merciful than his fellow Kingsmen, his personality changes to that of a homicidal maniac at the sight of his own blood, as evident at the time when he killed several of his own men and a bartender after he pricked his own hand with a shard of broken glass.

Heart fought Kenshiro in Shin's Palace at Southern Cross as the last of the Four Lieutenants. Normally Heart would be immune to the effects of Hokuto Shin Ken, but Ken used the the Hokuto Juha Zan to penetrate through Heart's flesh and devour his body. His last words before dying was "hidebu". Heart is one of the Four Chief Vassals of the King organization led by Shin, along with Spade, Diamond, and Club.