Not sure how a seminarian can be pressured into this. What's wrong with saying,, "Sorry, brah... I just ain't into that."
Brandi Williams
Emotional manipulation. This priest was older than these seminarians and they looked up to him as a mentor. That, amongst many other reasons, is why it's disgusting and wrong.
la verdad prevalece
St Bernardine of Siena: 'This Is the Worst Sin that exists':
"One who lives practicing the vice of sodomy will suffer more pain in Hell than anyone else, because this the worst sin that exists.
Facts Not Lies
Maybe it is a language barrier...

The word is not semInary (not with an 'e').
This "skinny-dipping" routine is an old grooming tactic to lower inhibitions. It was popular with clergy who ran the all-boys "Camp Fatima" .in NH. Students at the local Catholic all-boys high school used to sourly say Fatima needs a "G" instead of a "T".
Facts Not Lies
Archbishop Mitty High (was all male) had the mascot Monarchs... the locals called them the butterflies with similar implications.

Bellarmine College Prep (was all male) had the mascot 'Bell'... one can imagine how that was abused in a similar manner.

And, yes... skinny dips were alluded in casual conversations with both groups students.

Most took this with a grain of high school salt...
if its true the priest should be dismissed
Hugh N. Cry