We can't forget about our favorite closet murderer!
Lalli. Not the innocent Finn you'd like to believe! Who amongst us (besides me) would like to cuddle the most adorable mass-murderer this side of the safe zone?
Wahaha!
You definitely have a point. (Pff. It suits to all cats.
) And here we have the answer to "Why did he leave Emil and went upstairs?"
Maybe he just went to change. Every serial killer needs something to be remembered by - his "something" is the 'Ceiling-Crawling Tooth Fairy' disguise.
Apparently, he chose the wrong house to start his reign of terror, and had to fight for his place with the local drunk, who just wanted to crawl home (and soon will realise the burglary, after he successfully passes the corner of the corridor), and a strange girl with a very small vocabulary (at least she's mostly silent). As the jaw-dropping scene on pg. 260 proves, he won. (*COUGH*The Grudge, jawless scene, anyone?*COUGH*)