Nonlinear negative association
The graph is by no means linear. You can see that it has a bit of curve near the beginning.
Also, if you were to find the slope of the mainly linear line, you would find that it has a negative slope. You can also tell that it is negative because the y-values are decreasing as x values are increasing. And the slope is found by change in y over change in x. Therefore, the slope would be negative.
