  Spins constitute a group of quantum objects forming a key resource in modern
quantum technology. Two-dimensional (2D) van der Waals materials are of
fundamental interest for studying nanoscale magnetic phenomena. However,
isolating singular paramagnetic spins in 2D systems is challenging. We report
here on a quantum emitting source embedded within hexgonal boron nitride (h-BN)
exhibiting optical magnetic resonance (ODMR). We extract an isotropic $g$
factor close to 2 and derive an upper bound for a zero field splitting (ZFS)
($\leq$ 4 MHz). Photoluminescence (PL) behavior under temperature cycling using
different excitations is presented, assigning probable zero phonon lines (ZPLs)
/ phonon side band (PSBs) to emission peaks, compatible with h-BN's phonon
density of states, indicating their intrinsic nature. Narrow and inhomogeneous
broadened ODMR lines differ significantly from monoatomic vacancy defect lines
known in literature. We derive a hyperfine coupling of around 10 MHz. Its
angular dependence indicates an unpaired electron in an out-of-plane
$\pi$-orbital, probably originating from an additional substitutional carbon
impurity or other low mass atom. We determine the spin relaxation time $T_1$ to
be around 17 $\mu$s.
