  We present an analysis of the optical and UV properties of AT 2020wey, a
faint and fast tidal disruption event (TDE) at 124.3 Mpc. The light curve of
the object peaked at an absolute magnitude of $M_{g} = -17.45$ mag and a
maximum bolometric luminosity of $L_{\rm peak}=(8.74\pm0.69)\times10^{42}$ erg
s$^{-1}$, making it comparably faint with iPTF16fnl, the faintest TDE to date.
The time from the last non-detection to the $g$-band peak is 22.94 $\pm$ 2.03
days and the rise is well described by $L\propto t^{1.8}$. The decline of the
bolometric light curve is described by a sharp exponential decay steeper than
the canonical $t^{-5/3}$ power law, making AT 2020wey the fastest declining TDE
to date. Multi-wavelength fits to the light curve indicate a complete
disruption of a star of $M_*=0.11M_{\odot}$ by a black hole of $M_{\rm
BH}=10^{6.46}M_{\odot}$. Our spectroscopic dataset reveals broad ($\sim10^{4}$
km s$^{-1}$) Balmer and He II $\lambda$4686 lines, with H$\alpha$ reaching its
peak with a lag of $\sim8.2$ days compared to the continuum. In contrast to
previous faint and fast TDEs, there are no obvious Bowen fluorescence lines in
the spectra of AT 2020wey. There is a strong correlation between the
MOSFIT-derived black hole masses of TDEs and their decline rate. However, AT
2020wey is an outlier in this correlation, which could indicate that its fast
early decline may be dictated by a different physical mechanism than fallback.
After performing a volumetric correction to a sample of 30 TDEs observed
between 2018 and 2020, we conclude that faint TDEs are not rare by nature and
that they should constitute up to $\sim$ 50 - 60 % of the entire population and
their numbers could alleviate some of the tension between the observed and
theoretical TDE rate estimates. We calculate the optical TDE luminosity
function and we find a steep power-law relation $dN/dL_{g} \propto
{L_{g}}^{-2.36}$.

High Energy Astrophysical Phenomena