THEO when you tell him you no longer want to be with him because he wasn't telling you the truth. He was a werewolf and couldn't risk your human life because of what he was.
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"I'm sorry, Theo. I just can't."
"I love you, Y/N. Please don't leave me, I'll tell you everything."
"You say that but you just tell me more lies. I'm so sorry, Theo, this is for the best."