Let $G$ be a simple graph with vertex $I$ and edge set $E$. I am defining $M(G)$ to be the quotient of the free monoid $I^*$ on $I$ by the relations $ab=ba$ and $c^2 = 1$ (empty word) whenever $\{a,b\} \notin E(G)$ and $c \in I$ is arbitrary.
I have the following questions about the monoid $M(G)$.
Is this monoid $M(G)$ well studied in the literature?
What are some algebraic combinatorics or general combinatorial significance of this monoid?
Thanks for your time and have a good day.