First of all, the term pedophilia erotica was coined in 1886 by the Vienna psychiatrist Richard von Krafft-Ebing in his writing Psychopathia Sexualis
The APA's Diagnostic and Statistical Manual of Mental Disorders 4th edition, Text Revision gives the following as its "Diagnostic criteria for 302.2 Pedophilia":
Over a period of at least 6 months, recurrent, intense sexually arousing fantasies, sexual urges, or behaviors involving sexual activity with a prepubescent child or children (generally age 13 years or younger).
The person is at least age 16 years and at least 5 years older than the child or children in Criterion A.
Do not include an individual in late adolescence involved in an ongoing sexual relationship with a 12 or 13-year-old.
Ephebophilia has been defined as a sexual preference in which an adult is primarily or exclusively sexually attracted to post pubescent adolescents. It comes from the Greek: (ephebos) variously defined as "one arrived at puberty", "a youth of 18 who underwent his dokimasia and was registered as a citizen (Athens)", and "arriving at man's estate"; and philia) "love". Despite this classical etymology it is a term of recent coinage, created by psychologist John Money in the late twentieth century.
The actual boundaries between childhood and adolescence may vary in individual cases and are difficult to define in rigid terms of age. The World Health Organization, for instance, defines adolescence as the period of life between 10 and 19 years of age, though it is most often defined as the period of life between the ages of 13 and 18.
The APA diagnostic criteria do not require actual sexual activity with a child. The diagnosis can therefore be made based on the presence of fantasies or sexual urges alone, provided the subject meets the remaining criteria.
Mr. Foley is an Ephebophile.
He has yet to deal with his sexuality, so gay might not be a term I would use on him. It would be much more appropiate to use the term: men who has sex with young boys. Gay has nothing to do with his mental condition; as roughly the same number of pedophiles and ephebophiles are heterosexual or homosexual.