Ephebophilia is when an older adult is sexually attracted to post-pubescent teenagers or adolescents but still biologically adults—usually those in the age range 15–19. https://simple.m.wikipedia.org/wiki/Ephebophilia
I believe that ephebophilia is not morally wrong as long as it’s between two consenting adults. For example if a 18 year woman wants to have sex with me a 26 year old man then I do not think it’s morally wrong because me and her are both consenting adults so what we are doing is completely harmless.
Culture and law aside, I think the real fear is that there’s a power imbalance that makes it questionably consensual, if you actually have such a relationship.