a0 is the punishment in Dante's Hell which resembles or contrasts the sin in which the person created while on Earth.

Estige, the river of boiling blood, is the punishment in Dante's Inferno that resembles or contrasts the sin in which the person created while on Earth.

Explanation:

At the entrance to the fifth circle of hell is a waterfall of bubbling, boiling water and blood whose water was darker than purple. The water descends some beaches and forms a lake called Styx, where the accused are accosted with rage, who are together beating themselves and torturing themselves in an endless rage. At the bottom of the Styx are the spiteful ones who never showed their anger; they can not rise to the surface and stay in the mud at the bottom of the river, releasing the bubbles that are seen on the surface.