The Tower

That must be the Tower from "Swan Meat". 

I don't think it looks like a Castle. 

This Tower was where Sergei the insectivorous Creature Child 

running up the Stairs 

in order to escape from the wicked black Stuff. 

The Tower was very tall 

and there was a House leaned to the right. 

There was Sergei on the Roof of the Tower right next to the Chimney 

and there was a black Stuff changed into a Cobra Form to strike Sergei. 

The black Stuff wants to eat Sergei by changing into a Cobra Form and the final Form like the Demon Monster.