Tom's Severed Finger is an optional quest item that can be used during Beauty And The Beast in Divinity II: Flames of Vengeance.

After dealing with Taurus when he and Tom are encountered near Decimus' House in Crow's Nest, Tom pleads for your help to rescue his girlfriend Anne, who is being held prisoner by Luxurius.

Taurus had mentioned that he was to return to Luxurius' Mansion on Lanilor Lane with Tom's Severed Finger as proof as his death. If you choose to cut off his finger and use it to bluff your way into the mansion you receive lesser quest rewards but get the contents of a golden chest that otherwise cannot be opened. Alternatively, Tom can keep his finger and you can seek another way into the mansion.