Sally can't seem to avoid having an encounter with Donna on the season finale of Being Human. "Ruh Roh" is the 13th episode of the show's third season.
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Being Human Season 3 Episode 13 Quotes

I'm running out of ways to trust your girlish need for privacy.

Kat

Liam: I've made my peace with your desire to co-mingle with the vampires, but this connection that you've made with your blood - it's deadly.
Nora: Because of how it cures the virus?
Liam: It's not a cure, it's a curse.