Even if there is more to this than expressed by the poster, which I'm sure there is. I still take the view that as a 22 year old with a 17 year old, it's most likely to be a clumsy and immature man, rather than an evil man. I therefore think that education should be the tool of the CPS and not a criminal charge that would permanently label the 22 year old as a paedophile.
I recognise that there are evil men out there who are out to do harm to females and Children. I would never offer those people a way out. But there are normal, reasonable guys who are just Clumsy and don't know how to behave.