Frank is the sole surviving skeleton guard from a necromancer's underground crypt lair. After the lair is raided by a band of heroes the necromancer in question does a quick disappearing act leaving Frank effectively unemployed...
So what does a skeleton guard do when it has no job?
It goes looking for its former employer to again give meaning to it's low level NPC existence.
Whereas Frank may be a low level NPC skeleton guard, Barkley is in fact a stray puppy with Epic level cuteness, and quite a bit of spunk.
There's a lot of attitude and a lot of love in this small little fluffy package and woe betide any who mess with someone Barkley calls 'friend'
Frank (Not So Skeleton)
At this point in proceedings we appear to know only a little as to Frank in his pre-undead days, other than he would seem to have been some sort of mercenary or caravan guard, and that he likes sleeping?
Violet (More than a barmaid)
Possessing plenty of sass, attitude and a mean right hook, Violet, it would seem is more than just your average bar maid. As to what here true background is, this is something we've yet to learn