The sawarineko (触り猫, lit., "hindering cat" or "harming cat") is an oddity that is known for their ability to drain the energy of its victims and suppress the abilities of other oddities. Although considered to be a relatively harmless entity compared to others, they can pose a greater threat at the right circumstances.
The only noted case of a sawarineko is that which came into contact with Tsubasa Hanekawa, which created her "alternate identity" Black Hanekawa. This particular sawarineko was described as being previously male before merging with Tsubasa; in which its gender was rendered vague through the resulting inception of the apparition, Black Hanekawa.
A sawarineko assumes the appearance of a domesticated cat with a pure silvery-white coat; one distinct trait that a sawarineko has is the absence of tail, although most people still fail to make a distinction despite this.
- Body Possession - The sawarineko merges its consciousness to a chosen person and has the ability to manifest itself through that person. While the sawarineko is in control of the person's body, the person's hair changes into the a silvery-white color similar to the coat of a sawarineko and the eyes change into a cat's eyes. The person's memories during the possession by a sawarineko is suppressed, causing them to not remember any activities the oddity performed while in the person's body. A sawarineko who possesses a person slowly overwhelms that person's consciousness until a complete merge is made, causing the victim to lose its existence.
- Superhuman Strength - A sawarineko possesses a degree of strength that far exceeds that of a normal human, and in some cases can overwhelm half-oddities and even weaker oddities as well. Even while in the body of a normal human, a sawarineko can exert power that the human body cannot under any circumstances.
- Energy Drain - The most known ability of a sawarineko, it allows the oddity to drain away the vitality and energy of a target, organic or otherwise, by simply touching them. In most cases, an energy drain is enough for any person to be hospitalized after an attack. Rarely, particularly in the case of Black Hanekawa, an energy drain can also suppress the abilities of other oddities, such as Koyomi's immortality. The energy drain used by a sawarineko carries the "harming" effect, compared to a vampire's energy drain that "nourishes" the vampire.