Deline was born to a noble Sith family on Dromund Kaas. When she was found to not be Force sensitive, her parents were beyond disappointed. While her mother effectively ignored her, her father went one step further and sent her off to the Imperial military and shortly thereafter disowned her from the family. While she did not inherit the Force abilities of her sister or brother (deceased), she possessed an incredible keen intellect that was recognized and she was brought into Imperial Intelligence.
Current History and Status
After the marriage of Melissande Irunel and Darth Raath, the patriarch of the Irunel household met a tragic end. Deline was reinstated to her family by her sister, the latter claiming publicly that family should stick together during tragedy. There are whispers, however, that the reinstatement was a bribe of some sort to keep quiet about some family secret, but there is no evidence as to what that may be.
More recently, the Agent has found herself as part of an arranged marriage to forge an alliance between her own house and another Sith house. She begrudgingly has gone along with these plans for now.
Deline is a cold-hearted bitch, by all appearances. She is incredibly analytical and pragmatic, perhaps to a fault. She greatly resents her sister's place in the world and believes that Melissande inherited everything - beauty, power, etc. - while she has nothing and gets by on her wits alone.