"How should I exit from this place?"
The butcher asked Alephee while still in his Life Drain enhancement mode. He was going to revert to his close combat mode just before getting back to where the other competitors were.
Eren stayed in his summoner class mode because he wanted to create an intentional trail using that as his class. This way, the historians would only find out the trail of summoner class ranker still being present, making Tim a mysterious person that died and lived at the same time. He was also going to use Potion of Innocence to make the matters blurry enough so that his version of the story holds up and doesn't get questioned later.
'Hmm. You obviously can't enter the previous entrance using your current ranking status. There's a way… or two… that you can use. It's where the right-most corner of the library building was supposed to be. Not too far from the spot where you took those books out."
