If you are low on salt, is it permissible to lick a sailor?
Yes, licking sailors is an effective and reasonable method of salt-replacement.
No, licking sailors is a ineffective and/or unreasonable method of salt replacement.
If you were to lick a sailor in order to obtain salt, would this be considered cheating on your significant other?
Yes, licking other people is inappropriate in the context of a committed and healthy relationship, even if you need more salt in your diet.
No, licking sailors for the purpose of salt-replacement is not a sexual action and therefore has no bearing on your relationship with your significant other.
It depends. It would only be cheating if you derived non-salt-based pleasure from the sailor-licking.