Additionally, each of [`relplot()`](../generated/seaborn.relplot.html#seaborn.relplot"seaborn.relplot"), [`catplot()`](../generated/seaborn.catplot.html#seaborn.catplot"seaborn.catplot"), and [`lmplot()`](../generated/seaborn.lmplot.html#seaborn.lmplot"seaborn.lmplot") use this object internally, and they return the object when they are finished so that it can be used for further tweaking.
The square grid with identity relationships on the diagonal is actually just a special case, and you can plot with different variables in the rows and columns.