How far will the joke go before i meet my new housemate

First let me introduce myself, i am a 29 year old Norwegian man who moved to the north of Sweden for a year for a technical education. I like pranks, sometimes taking them way to far also =)
The Sweedes are a funny people, they never ever say anything racist PC++ and very polite
From the school we get boxed in 2 people in one apartment (own bedroom)

When i came home today i discovered someone has moved in my house, so i went to cook, and no one came to greet me .

I went to my room put this beautiful song on repeat for the last 5 hours on my stereo. No complains yet.

As i feel like killing infadels right now and think i need to sleep on the idea of making a mock bomb, will update tomorrow

I have no idea what they are saying in the song, can someone translate ?
i am assuming he's finnish since he eats the dark bread. All the info i have about this guy are these pictures.

White shoes