Tharja is a Dark Mage in Fire Emblem: Awakening. She was a solider for the Plegia army during the Ylisse/Plegia war. She questions why she and her country are fighting against Ylisse. When she is confronted by Chrom she is reluctant to fight him. Sensing this Chrom calls out to her asking why she does not want to fight. After she admits that she rather not die for something she does not believe in Chrom asks her to join his team. When she asked if he fears that she may backstab him Chrom replies that he trusts her.
Tharja is a cold person towards most people, always having evil thoughts and threatens others with curses and hexes. She comes from a family of Shamans all which are experts in the dark arts. She is able to read fortunes and create potions, provided she has the ingredients. She does open up to people eventually, but only if they have a high enough support with her.
When she meets Robin (the Avatar) she becomes quite obsessed with him/her. Her obsession turns into stalking as she attempts to win Robin’s affection. For example she can recall several little things Robin has done including how many times s/he had turned during the night. This leads Robin to ask her to act more normal, which she attempts. However, this Tharja becomes even creepier to Robin so she quickly reverts back to her old personality. Later on Tharja finds Robin passed out with a fever in which she cures him/her with a cooling hex. She fears Robin would blame her for the curse, but Robin assures her that s/he does not believe it to be the case. If Robin is a male and reaches S support Robin will propose to her meaning she has succeeded at winning Robin’s affection.
"You're already dead..." - Tharja