This is what box looks like when happily sited and not clipped. It's really quite a nice thing, especially when it turns blue like this one has. The species is also treelike when old enough, in a suitable situation (good soil, left unmolested etc.). I have seen a few down here about 6m high.
Here's a nice mature box for you, about 8-9m tall, to show the natural growth form. Photo from last spring.