Name: Vampyric Bracelet
Sell value: 6000g
Effect: Absorbs 8% of damage dealt as HP.
Level required: 40
There is no specific enemy that drops this item. It is only found as a random accessory drop from enemies above level 100 (only found in the Tower of Heaven on advanced mode), or from treasure chests on floors 53-58 of the Tower. Floors 59 and 60 have no chests, but do have enemies above level 100.
There is the possibility that enemies below level 100 might drop it, but given how rare this accessory is, I doubt it. You'll have to fight plenty while going through the Tower, though, so who knows, you may get lucky. It might also be found as treasures on floors below 53, but again, I'm not sure. The best bet would be to retreat at the start of 53 and repeatedly run 53-60, killing everything up through the Archangels on 60 (but ignore the Dark Dragon, as it will never drop accessories). Eventually you'll get it.
I got two of these bracelets:
-One dropped from an Archangel on floor 47.
-The other dropped from a treasure chest on floor 53.
I'll be uploading a save to GameFAQs sometime in the next week or two with the Vampyric Bracelet, and all other accessories and unique equipment. Anyone who has a PS2 Max Drive, Codebreaker, or other way of using a save can download it and copy it to a memory card, then trade the Vampyric Bracelet and any other items of their choosing to their own file.
If anyone is interested in getting a not-quite-finished version of this save sooner, send me a PM on here and I can email it to you.