Blobs haven't been relevant since iOS 7 when APTicket replaced them. Apple does not use them for authentication anymore.
That said, there is Odysses. Unfortunately, while your device is 32-bit Apple is not signing iOS 8.4.1 for the iPod Touch 5g.
Even more unfortunate for you, to even BEGIN this process you need to be jailbroken first. And since you are currently on iOS 9.2.1, well, you don't have a jailbreak. And since Apple isn't signing 8.4.1 for the iPod Touch 5G it doesn't matter anyway.