Cats who live outside of the Clans are categorized into three groups. Housecats, referred to as "kittypets" by Clan cats, are often looked down upon by the Clan cats for their cozy and lazy lifestyle. "Loners" are feral cats who live outside of the Clans, usually by themselves. They are often regarded by the Clans with suspicion. Similar to loners are "rogues", who differ in that they try to cause the Clan cats harm. In some cases, these cats may form groups, such as The Sisters (a group of female cats who live together), The Kin (a group of violent rogues), BloodClan (another group of violent rogues) and The Guardians (a group of cats who heal others and avoid conflict). It is rare, though not unheard of, for a kittypet, loner, or rogue to join a Clan, as outsiders are generally distrusted by Clan cats. In several instances, Clans that have taken in outsiders have been met with scorn by the other Clans.