Necrosadism

... necrosadism, arousal from mutilating a corpse. All these features were typically displayed by Jack the Ripper, the notorious late nineteenth century killer.

Source: wiktionary

Necrosadism (sexual gratification from the mutilation of corpses). These terminologies often overlap and, in Bertrand's case, they form part of a sexual trilogy in which necrophagy and necrosadism combine to create necrophilia[…]

Source: wiktionary

[…] Correlated with necrosadism. / Necrophilia: Arousal through engaging in sexual acts with or being intimately connected to human corpses. Correlated with numerous necrophilic spectrum behaviours, including necrosadism. / Necrosadism: Arousal or preoccupation with committing indignities to or defiling and/or mutilating and humiliating dead bodies. Correlated with erotophonophilia, odaxelagnia, and cannibalistic behaviours not otherwise classified.

Source: wiktionary