Boon Companion for Black Blades?

[Tom S 820]

Boon Companion
Your bond with your animal companion or familiar is unusually close.
Prerequisites: Animal companion or familiar class feature.

Benefit: The abilities of your animal companion or familiar are calculated as though your class were 4 levels higher, to a maximum effective druid level equal to your character level. If you have more than one animal companion or familiar, choose one to receive this benefit. If you lose or dismiss an animal companion or familiar that has received this benefit, you may apply this feat to the replacement creature.

Special: You may select this feat more than once. The effects do not stack. Each time you take the feat, it applies to a different animal companion or familiar.

By the RAW I would say no. But the base idea is the same?
The Black Blade is pet like and serves the same role.

[Dragonamedrake]

PFS ... probably not.

In a home game. I would allow it. If your Blackblade Magus wanted to Dip it would be a nice way to keep your Blade up to your character level. I dont see it as a huge deal.

[Tom S 820]

I only taking about home game or AP.

[darkwarriorkarg]

Sounds reasonable, and is more restricted, as no other class can have it, so I'd allow this:

Curse of the Black Blade
Your black blade shares a part of your soul
Prerequisites: Black Blade class feature
Benefits: The abilities of your black blade are calculated by your character level, and not your levels of bladebound magus archetype.

[ShadowcatX]

Like Dragonnamedrake I wouldn't have a problem with it in a home game.