[karnage]

According to coppers I know, many home invaders and burglars leave sphincter souvenirs at the scenes of their crimes. A form of humiliation for the victim. This sounds like a vile variation of a familiar theme.

[RegulatorCountry]

Revelling in their own filth is something beyond just an attempt at humiliation, I'd think.

[Question_Assumptions]

They did that to my grandparent's house when they robbed it. The police should start DNA testing of any feces they find. It might help them find patterns to burglaries.