I agree with timmyelliot. In fact, I would say you’ve given us TOO MANY set ups:

1) wedding plans fall off
2) a casual sexual encounter gone wrong
3) pissing off a mob boss

I think you need to do one of two things.

First – you need to decide whether all the set up stuff is just guff, and if so, then get us to the island with the nuns as soon as possible. As timmyelliot suggests, you still need goal for your protagonist to be working towards once he gets there. At Karel’s Story Series class, he suggests thinking of the “goal” or “action” section of the logline as your second act. What actually HAPPENS in your movie?

Second – if you decide that all that set up stuff is important, and you want the first half of your film to focus on his sexual escapades, you need to realize that the character’s goal SHIFTS at the midpoint, and reflect that in the logline. So:

“After his engagement falls apart, a boozehound casanova tries to forget his woes by seducing every women he meets. (First goal). But when his one night stand turns out to be the daughter of an homicidal crime boss and is forced to flee to an island full of nuns (midpoint), he must gain control of his sex drive or risk being sent back to face a grisly death. (Second goal).”

I’ll be honest, it still feels like there are too many setups – like the meat and potatoes of your film starts with him needing to leave because of the crime boss (at around the middle to end of act 1), and the nunnery taking up the next hour and a bit of your film.

In your original logline, you’ve named your protagonist. It’s better not to, but instead to tell us WHO he is and WHAT his character flaw is. This can usually introduce some irony into the logline (I went with a casanova; only because it’s the type of person I imagine having the hardest time on an island full of nuns).

I like that it’s sort of American Pie meets Sister Act – could be an interesting project.