Knowing somewhat the writing style of this author, I won't particularly pay much attention to this new guy, but still, you have no fucking right acting to MC this way, if it was MC who suggested FMC to stay then ok, fine, you can go ahead and do that, in fact, it would not be normal if you didn't act like that.
But FMC was the one insisted on staying, if a alligator threatens to attack you but you still keep swimming in its pond despite the warning, the alligator is not to blame here if it eats you, the blame falls on you.
When next chapter come out and it reveals that FMC didn't tell him that she was the one insisted on staying (which I'm 90% sure was the case.), in that case then I will accept your behaviour, but if you already knew FMC was the one wanting to stay and still act to MC this way then you need some senses beaten into you.