Iso onna (Japan)

Iso onna are dangerous, siren-like yokai indigenous to Kyushu Island of Japan. Their descriptions vary, but the most common depiction portrays them as beautiful, nude women with long, black hair. At first glance, they appear indistinguishable from ordinary women—except for their blurry, translucent appearance from the waist down.

Approaching an iso onna is a fatal mistake; she will drown her victim and drain their blood.