Jack the Ripper is a mid-tier undead being that Ainz Ooal Gown's summoned during the cemetery incident. It has green hair that grows upwards like the pattern of a flame and long angular elf-like ears. Its face is cover completely by a white smiling mask with yellow eye holes and is dressed in a black overcoat with purple outlines and white buttons. The tips of its fingers are all covered with sharp blades. As a mid-tier level undead, it easily overwhelms its low-tiered skeleton opponents. Jack the Ripper has a very thin body frame and seems to lack muscles, but it makes up for it with its lightning speed agile movements and deadly precision attacks. It can be heard laughing hysterically as it fights. (Source: Overlord Wikia)