Nicholas Julius 565's page

It only works on fey, as per the Target line.

The Serpentine bloodline arcana does not help because it makes animals etc be affected as if they were humanoids, and humanoids are not affected by charm fey.

Secrets of the Grave just makes undead be affected as if they were alive, not as if they were every possible type of living creature. It will not help with charm fey.

But then Charm Person does work on Animals in this case...

Ok Obviously the answer should be no but would the Charm Fey Spell work animals, magical beasts, Monstrous Humunoids & Undead with Serpentine Bloodline & Dirge Bird's Secrets of the Grave...

Charm Fey
School enchantment (compulsion) [mind-affecting]; Level bard 1, sorcerer/wizard 1

CASTING

Components V, S
Target one fey creature

DESCRIPTION

This spell functions as charm person, except it affects a fey instead of a humanoid.

Serpentine:
Bloodline Arcana: Your powers of compulsion can affect even bestial creatures. Whenever you cast a mind-affecting or language-dependent spell, it affects animals, magical beasts, and monstrous humanoids as if they were humanoids who understood your language.

Secrets of the Grave (Ex)
A dirge bard may use mind-affecting spells to affect undead as if they were living creatures, even if they are mindless (though spells that affect only humanoids do not affect them, even if they were humanoids in life).