A simple corner tower module using rounded tower bits from Harry Potter sets. The most annoying thing was not being able to join the round tower element to the square wall elements. The ladder is actually a structural support as it holds the tower against the walls.
Another workaround is the tall white pillar supporting the tower platform. I would have rather built some sort of interior support or detail or at least used a grey or black element but the lack of support meant that I thought it best to use the large pillar and all I had was white.