|Dates||???? - 2017 (killed by Dean Winchester)|
|Location||Eureka Springs, Arkansas|
|Episode(s)||12.11 Regarding Dean|
Catriona Loughlin was a witch and member of the powerful Loughlin family. A hundred years ago, the Loughlin family made their way from Ireland to a small town on the Mississippi Delta, where they amassed great power through the use of the Black Grimoire. The family was eventually killed by hunters, leaving Catriona, Boyd and Gideon Loughlin as the surviving heirs to the Black Grimoire.
Boyd and Catriona Loughlin find Gideon's body. Boyd blames Catriona for Gideon's death because she killed the accountant even though Gideon had asked her not to. They take the body back to the Loughlin residence, there Catriona prepares Gideon's body to be resurrected using the Black Grimoire. When Sam arrives at the home, and threatens Catriona with the witch-killing bullets, he is quickly incapacitated and restrained, so Boyd can perform a ritual to swap Sam's soul for Gideon's and resurrect him. Rowena arrives, Catriona and her have a confrontation. Catriona has Rowena pinned to a wall throwing broken glass at her when Dean arrives, killing Catriona with a witch-killing bullet.