
Pan, definitely not a Kitsune |

I was going to put this unter "Rules Questions", but I noticed that it's mostly just me ranting, so I'm posting it here instead…
Let's assume I have the improved version of the Wasp Familiar (either by being a 5th level caster with a regular familiar who took that feat, or by being a 7th level level character who took it twice).
The feat says to "use the statistics for an imp, but replace the invisibility spell-like ability with an unnatural lust (DC 14) spell-like ability usable three times per day."
The unnatural lust part is easy. But the "use the statistics for an imp" is… weird.
Let's compare: Here's the Imp
Is this wasp an outsider with the devil subtype? Because the imp is. (Magical Beast (Chaotic) could work, though.)
Also, I hope they don't mean alignment, because lawful evil doesn't suit Calistria's servant. (Same about the alignment subtypes, which should be Chaotic, if anything.)
It also has damage resistance "good or silver" - again marking it as lawful evil (chaotic creatures usually have their DR bypassed by Cold Iron, so "lawful or cold iron" would be appropriate).
And Calistria's servitor outsiders are usually immune against diseases, and resistant/immune to electricity. (Immunity to poison fits, though.)
Basically… the resulting stats would be a thematic mess.