Generally speaking, when someone asks "Do you think this will break Rule 7?"... then answer (even without looking at the picture) is Yes.
There are games where you might do a double-take as a player, but in those cases the author didn't think to ask and generally on reflection, those characters are depicted as over 18.
But where an author both knows Rule 7 exists and then comes on here asking... That's always a clear sign that author is intent on pushing the limits.
And yeah, I thought girl too - then I read the OP's post refer to the character as "mc" and figured boy.
Either way - the rule exists to avoid the "elder god pretending to be a 7yr old girl" or "50yr old man's magically able to make himself appear any age he likes".