Age of consent is 16 here so this argument does not apply and the 18 year old would not be a pedo by any means according to the law. Also you are confusing pedophilia with ephebophilia here. If it were my decision I would say no even with sexual contact because they are extremely close in age to the point where its not really an issue and more of a gray area.
1st it is 1 year age difference, So it isn't that concerning. But if they have sexual contact before the 17-year-old becomes 18, Then yes, The 18 year old is a paedophile since he is having sexual contact with an underage, Eve f there is only 1 year difference in age.