Slutty Servant
That Kate would attack him despite her fear of the power he had revealed last night wasn't surprising to Blake, after all, she was a woman of opportunity.
The method of corruption involved two steps, the first being the usage of blood, a method involving the target consuming the user's blood and the second step was through the use of a soul mark, a mark whose creation was so complex that all Blake could do was follow the systematic information that had been put into his head, and create it, the young champion not having a single iota of Knowledge on it's workings.
For Kate's corruption, with Blake knowing that she would never consume his blood of her own accord, he decided to use a bit of acting and emotional manipulation to get the woman to do it of her own violation.