Canada, for example, has "close in age exception"s. Specifically, age of consent is 16, but "a 14 or 15 year old can consent to sexual activity as long as the partner is less than five years older and there is no relationship of trust, authority or dependency or any other exploitation of the young person."

https://www.justice.gc.ca/eng/rp-pr/other-autre/clp/faq.html