  The detection of gravitational waves from neutron star merger events has
opened up a new field of multi-messenger astronomy linking gravitational waves
events to short-gamma ray bursts and kilonova afterglows. A further - yet to be
discovered - electromagnetic counterpart is precursor emission produced by the
non-trivial interaction of the magnetospheres of the two neutron stars prior to
merger. By performing special-relativistic force-free simulations of orbiting
neutron stars we discuss the effect of different magnetic field orientations
and show how the emission can be significantly enhanced by differential motion
present in the binary, either due to stellar spins or misaligned stellar
magnetospheres. We find that the built-up of twist in the magnetic flux tube
connecting the two stars can lead to the repeated emission of powerful flares
for a variety of orbital configurations. We also discuss potential coherent
radio emission mechanisms in the flaring process.
