i mean, it never happened but, if it does, i would run out of the bathroom fast AF and go grab the sharpest knife in kitchen (we have very light and super sharp knifes) and stab him (if he has a knife too) although i didn't try killing before but i have to in this moment and i won't go to jail as it was self defense. i actually don't know what to do if he has a gun other than running out closing the door finding the closest phone, go to my parents room (the only one with a lock) and just call the police and hold off until they reach my location. note: I'm good dodger not that good but good enough to dodge his cheap attack ( most killers attack weakly if their target's weapon is weaker ). that's what i would do. or just cough y'know.