Whether or not it is morally wrong is up to you to decide. Legally speaking (in the US), a person is able to consent to sex if they are at least 18 years old, so any sex that occurs in this relationship is completely legal.
Well, for starters, it's illegal.
YES espicially if your sexually involved its called sexually abusing a minor
While some claim it is morally wrong, it is a state of mind and entirely up to the people in the relationship, and the opinions of others.
NO! What is so wrong about it? Everyone is equal!
Its your choice. It is a little strange but no one can tell you whether its right or wrong.
Well if they're both happy and neither care about the age I don't see what's wrong with it
Of course not.
It is legal to date a 21 year old man if you are a 17 year old girl. It is not legal to engage in certain activities with a 21 year old man as he could be prosecuted.
NO
yes
Yup :D
no that will be weird