  Binaries containing a compact object orbiting a supermassive black hole are
thought to be precursors of gravitational wave events, but their identification
has been extremely challenging. Here, we report quasi-periodic variability in
X-ray absorption which we interpret as quasi-periodic outflows (QPOuts) from a
previously low-luminosity active galactic nucleus after an outburst, likely
caused by a stellar tidal disruption. We rule out several models based on
observed properties and instead show using general relativistic
magnetohydrodynamic simulations that QPOuts, separated by roughly 8.3 days, can
be explained with an intermediate-mass black hole secondary on a mildly
eccentric orbit at a mean distance of about 100 gravitational radii from the
primary. Our work suggests that QPOuts could be a new way to identify
intermediate/extreme-mass ratio binary candidates.
