In this construction project, they will be using thread to hold everything together. The color of the thread is a deep red, and it gives everything a crimson look.
You're done, and the whole building is a deep red crimson color (it takes a lot of thread to hold a whole building in place). It's time to show the client, Emperor こういち, the finished product.
Currently there are no similar looking kanji which exist in the WaniKani learning system