What if the artist themselves are the ones that muddle the ToS? My concern was because one of them forego her own ToS when she asked for some favors (money amongst other things) outside the normal process, as such, it was a special kind of commission that the artist herself proposed.

I had already helped her out before, so when she needed my help again, she offered the "commission" as a way to repay the favor. Being that the friendship went south eventually and that it was not a proper business transaction, I ended up with the short end of the stick.