  We investigate the generalized parton distributions (GPDs) with non-zero
$\xi$ and $\Delta^\perp$ for a relativistic spin-1/2 composite system, namely
for an electron dressed with a photon, in light-front framework by expressing
them in terms of overlaps of light-cone wave functions. The wave function
provides a template for the quark spin-one diquark structure of the valence
light cone wave function of the proton. We verify the inequalities among the
GPDs with different helicities and show the qualitative behaviour of the
fermion and gauge boson GPDs in the impact parameter space.
