  Antiferromagnets exhibiting giant anomalous Hall effect (AHE) and anomalous
Nernst effect (ANE) have recently aroused broad interest, not only for their
potential applications in future electronic devices, but also because of the
rich physics arising from the Berry curvature near the Fermi level.
$\rm{Co_{1/3}NbS_2}$, by intercalating $\rm{Co^{2+}}$ ions between $\rm{NbS_2}$
layers, is a quasi-two-dimensional layered antiferromagnet with a chiral
lattice. A large AHE has been observed in $\rm{Co_{1/3}NbS_2}$, but its origin
is under debate. In this letter, we report the large AHE and ANE in exfoliated
$\rm{Co_{1/3}NbS_2}$ flakes. By analyzing the thermoelectric data via the Mott
relation, we determined that the observed large AHE and ANE primarily result
from the intrinsic Berry curvature. We also observed the magnetic domains in
$\rm{Co_{1/3}NbS_2}$ by reflective magnetic circular dichroism measurements.
Combined with electrical transport measurements, we confirmed that the magnetic
reversal in $\rm{Co_{1/3}NbS_2}$ is determined by domain wall motion, and the
critical field ($H_c$) exhibits a memory effect of consecutive magnetic sweeps.
Our work provides insight into the topological properties of
$\rm{Co_{1/3}NbS_2}$ and paves the way to studying the spin configuration and
magnetic domain dynamics in this fascinating antiferromagnet.
