A list of peope that a person wants to have have sex with, no matter the circumstance or their relationship status. (Which is much better than the "one free pass" some would normally get.) In this case, the list can be celebrities or just regular people. Ideally, if in a relationship, both parties would have such a list.
"I'm sorry, hun. I know we're getting married tomorrow and she's one of your best friends, but she's on my fuckit list. Given the fact she lives out of the country, this may be my only opportunity to have sexual relations with her."