Deep exclusive photo-production of lepton pairs off the nucleon, the $\gamma N \to \gamma^* N \to e^+ e^- N$ reaction, is sensitive to the nucleon partonic structure at high $\gamma^*$ virtuallity. This reaction is dominated by the Bethe-Heitler like process where the incoming real
photon splits into a lepton pair in the nucleon field. It interfers with Timelike Compton Scattering, where a real photon is scattered off a quark from the nucleon and a virtual photon is emitted, then decays into a
lepton pair. We studied the correlations between decay angles of the leptons, and between decay angles and kinematic variables in the lab frame. The goal of this work
is to make predictions for designing future experiments, and to accompany current data analysis involving exclusive lepton pairs production. We present our interpretations of the lepton pair angular behaviour, we discuss the kinematic and angular dependencies of the unpolarized BH cross section, and the correlations between different variables.
We propose tools for data analysis. All calculations have been made at typical kinematic for JLab 12 GeV experiments and our results can be applied for any experiment in an equivalent kinematic domain.