In a unity-gain feedback control system, the plant
\[
P(s) = \frac{0.001}{s(2s + 1)(0.01s + 1)}
\]
is controlled by a lag compensator
\[
C(s) = \frac{s + 10}{s + 0.1}
\]
The slope (in dB/decade) of the asymptotic Bode magnitude plot of the loop gain at \( \omega = 3 \, \text{rad/s} \) is _________ (in integer).