That depends on where you live.
it is not illegal for a 16 year old and a twenty year old to be together in England
no it is not illegal four a 21 year old and a 16 year old to be going out.
no it is not illegal. it would most likely only be illegal if the 16 year old turned 18 and the girl is still only 16 or 17.
It is not illegal for a 26 year old to date a 16 year old. However, it is illegal for a 26 year old to have sexual relations with a 16 year old and considered statutory rape, even if it is consensual.
No. now to have sex with that 16 year old, depending on the country, is illegal
No, not if the parents of the 16 year old approve of it.
No
no
No
Of course not !!
not really
No