Not knowing where you live, this may not apply; but, if in the UK, start a log (diary) of the events and inform your local police. If you are a member of a minority community (BME, gay, etc.) contact 'Stop Hate UK' (Google will give you the freephone number). Additionally, your local Social Services may be able to help, or point you in the right direction.
Not necessarily - but it could be. On the other hand - are you annoying the neighbors to the point where they call the police and then you stop when you know the cops are coming?? See!That's exactly what the police have to decide and deal with when the arrive.
Block the user
No. not unless you tell him to stop and he keeps putting it there then it might just be harassment but if he moves it up your leg and you tell him to stop but he doesn't then it may count as sexual harassment.
After several attempts, it can be considered harassment.
Yes, it is considered sexual harassment. Even if they ask you one time, and you do not appreciate it, it is still technically considered sexual harassment.
YES
slap him in front of everybody or tell your parents .
Yes you can call the police and say that your neighbors are disturbing the peace.
If the woman does not consent (i.e. say "yes" out loud) or flirt back, then yes, it is sexual harassment.
keep it in a different field
Tell him to stop bothering you or you will report him for harassment. Simple.
There are many types of different things you would need for a harassment lawyer. Some things one would require a harassment lawyer for is sexual harassment, civil harassment and job harassment.