I refuse to believe Mai is not fucking with Tae.
For one, it's more likely for adult to be mistaken for grade-schooler, than the other way around. But also all those mind games.
I only check it now to see if the author finally spills the beans and be like "yeah, she's actually 24" and teaches grade school or something like that.
I will not believe she's 10, until Tae actually sees her attending class, in the uniform and all that. Preferably while she holds her birth certificate.