  In its Campaign 9, K2 observed dense regions toward the Galactic bulge in
order to constrain the microlensing parallaxes and probe for free-floating
planets. Photometric reduction of the \emph{K2} bulge data poses a significant
challenge due to a combination of the very high stellar density, large pixels
of the Kepler camera, and the pointing drift of the spacecraft. Here we present
a new method to extract K2 photometry in dense stellar regions. We extended the
Causal Pixel Model developed for less-crowded fields, first by using the pixel
response function together with accurate astrometric grids, second by combining
signals from a few pixels, and third by simultaneously fitting for an
astrophysical model. We tested the method on two microlensing events and a
long-period eclipsing binary. The extracted K2 photometry is an order of
magnitude more precise than the photometry from other method.
