Have pic related

that's a canker sore, it will resolve itself in a week or two.

It's a fucking cold sore you have nothing to worry about

They're human beings lmao. Significant amount of them probably wash their hands after that, but if they hate their job, why would they?

that's just a canker sore you retard

>They're human beings
ehhh...

it will go away by itself, don't worry about it, i hate these couple of times

that's normal and common, goes away after a while.

Certain ingredients in some toothpastes can make you more likely to develop canker sores, especially if you aren't rinsing with water after brushing.

isnt overbite when front teeth are behind bottom teeth? in OP's picture you can see only his lips like that

no, it's the opposite. he is right

That isn't sexually transmitted. It's just an ulcer / canker sore. Everybody gets them. Probably damaged the tissue when you were eating. It'll heal in a few days.

Not OP, but how do I fix that

this is just a normal mouth ulcer you idiot. it's caused by acidity imbalance in your saliva.

>our mouths are acidic

this isn't your fantasy monster, fucking retard

youre fine retard