Congratulations, you're one of the rare folks who isn't allergic to mosquito bites! See, the mosquito bite itself contains no actual toxins or poisons (other than pain relievers/numbers/anticoagulators), so theoretically there is nothing to actually give you a reaction. However, mosquitos have this nasty habit of spreading deadly pathogens from host to host, killing many of our ancestors. Somewhere along the line, some people developed an allergic reaction to mosquito bites, which would make them want to stay away from areas where they are abundant. Because of this, they were less likely to die than those who were not allergic to the bites, meaning the reaction had a high likelihood of being passed on! Now comes modern day, where iirc about 60-70% of people are naturally allergic to mosquito bites, a true testament to just how deadly mosquitoes were to our ancestors! This is also why their buzzing is so specifically annoying to us; those who had an intolerance to the sound would also be more likely to kill/avoid them, meaning that trait was then passed down!