  We identify a fading AGN SDSS J220141.64+115124.3 from the internal Product
Launch-11 (MPL-11) in Mapping Nearby Galaxies at Apache Point Observatory
(MaNGA) survey. The central region with a projected radius of $\sim$2.4 kpc is
characterized as LINER-like line ratios while the outskirts extended to
$\sim$15 kpc show Seyfert-like line ratios. The [OIII]$\lambda$5007 luminosity
of the Seyfert regions is a factor of 37 (2) higher than the LINER regions
without (with) dust attenuation correction, suggesting that the AGN activity
decreases at least $\sim$8 $\times$ 10$^3$ yrs ($\sim$2.4 kpc/light-speed) ago.
We model the emission line spectra in the central region with double Gaussian
components (a narrow core and a broad wing) and analyze the properties of each
component. The narrow core component mostly co-rotates with the stellar disc,
whereas the broad wing component with a median of the velocity dispersion
$\sim$300 km s$^{-1}$ is related to a wind outflow. The kinematic position
angle (PA) of the ionized gas shows a $\sim$20{\deg} twist from the galaxy
center to 1.5 effective radius. The median of the PA difference between the gas
and stellar components is as large as $\sim$50{\deg} within 0.4 effective
radius. The tidal feature in DESI image and star-gas misalignment suggest this
galaxy is a merger remnant. Combining all these observational results as well
as public available X-ray and MIR luminosities, we confirm this is a fading
AGN, the merger process kick-started the central engine to quasar phase which
ionized gas composed of tidal debris, and now the activity of the central black
hole decreases. The discontinuity in [OIII]$\lambda$5007 flux and EQW maps is
due to multiple AGN outbursts triggered by merger remnant gas inflows.
