  Magnetic massive stars comprise approximately 10% of the total OB star
population. Modern spectropolarimetry shows these stars host strong, stable,
large-scale, often nearly dipolar surface magnetic fields of 1 kG or more.
These global magnetic fields trap and deflect outflowing stellar wind material,
forming an anisotropic magnetosphere that can be probed with wind-sensitive UV
resonance lines. Recent HST UV spectra of NGC 1624-2, the most magnetic O star
observed to date, show atypically unsaturated P-Cygni profiles in the Civ
resonant doublet, as well as a distinct variation with rotational phase. We
examine the effect of non-radial, magnetically-channeled wind outflow on
P-Cygni line formation, using a Sobolev Exact Integration (SEI) approach for
direct comparison with HST UV spectra of NGC 1624-2. We demonstrate that the
addition of a magnetic field desaturates the absorption trough of the P-Cygni
profiles, but further efforts are needed to fully account for the observed line
profile variation. Our study thus provides a first step toward a broader
understanding of how strong magnetic fields affect mass loss diagnostics from
UV lines.
