Walking into potions and seeing Horace Slughorn where Severus should have been was like an ice pick being rammed into the namesake's solid substance, that certain crack and break you know is eventual. Something was going to happen that Slughorn being here was crucial to the start of, Hermione could feel it. Him being here was the certainty that Dumbledore expected Severus to not be back next year, he thought he would lay his life down for him in order to win this war. Hermione would not allow that to happen. Would not allow him to lay down his life for her, nor anyone else no matter the promises he made. Especially a man who deceives by pretending to be good, when in reality, he is the one to send people off to their deaths.