Many people were wondering, who can this springlock body belong to. Well, I have a theory

Many fans are thinking, that this suit is Funtime chica. But actually there aren't any proofs of Afton's runtime Chicago existance. We don't her on blueprints, and no one even memorizes her in entire fnaf.

So, I think this suit belongs to earlier version of Baby.

As we know, after getting rejected out of Ennard, Baby returns to Circus baby's entertainment and rental, to collects new body parts and suit.

And the suit Baby actually wears in FFPS can possibly be old spring suit of Baby.

+If you compare suit's face to Scrap Baby's, you can find many similar things

Like Baby said in night 4, this came from her old pizzeria. This can possibly be an old design of Baby, or her prototype.

So, that's the origin of spring suit

But remember this is just a theory

A Vlad's theory