  We have collected 10025 foreground-background quasar pairs with projected
distances $d_p<500$ kpc from the large quasar catalog of the SDSS DR16Q. We
investigate the properties of the Mg II absorption lines with $W_r>0.15$ \AA\
around foreground quasars, including both the LOS (line-of-sights of foreground
quasars) and transverse (TRA, perpendicular to the LOS) absorptions. Both the
equivalent width (the correlation coefficient $\rho=-0.915$ and the probability
$P < 10^{-4}$ of no correlation) and incident rate ($\rho=-0.964$ and $P <
10^{-6}$) of TRA \Mgii\ absorption lines are obviously anti-correlated with
projected distance. The incident rate of TRA \Mgii\ absorption lines is
obviously ($>4\sigma$) greater than that of LOS \Mgii\ absorption lines at
projected distances $d_p<200$ kpc, while the TRA and LOS \Mgii\ both have
similar ($<3\sigma$) incident rates at scales $d_p>200$ kpc. The anisotropic
radiation from quasars would be the most possible interpretation for the
anisotropic absorption around quasars. This could also indicate that the quasar
radiation is not obviously impacting the gas halos of quasars at scales
$d_p>200$ kpc.
