As it turns out, Slendy is actually a foulmouth- in German.
(Quick backstory- the origin of the 'slenderman' originates in Germany (unless I am greatly mistaken) so it makes sense that Slendy would speak fluent German)
Well whaddya know whaddya know I actually managed to fill up an entire book with these bloody headcannons. An... More
As it turns out, Slendy is actually a foulmouth- in German.
(Quick backstory- the origin of the 'slenderman' originates in Germany (unless I am greatly mistaken) so it makes sense that Slendy would speak fluent German)
Fanfiction