Timotheos, I appreciate your response but it seems to have missed something.
Per Revelation 20:9-10, the problem presented for you is that if what God would do to one person he could do to any person. It defines his character. So even if you reason that "only the devil will endure Eternal Conscious Torment" you still have a God of Eternal Conscious Torment.
Yes, you do have many (many) passages saying that the wicked will be destroyed. You needn't quote them all here. However, aren't you forgetting something? The devil is the definition of wicked. If the devil will not be destroyed, than what of the rest of the wicked?
Yes, Romans 6:23 does say that the wages of sin is death. But hasn't the devil also sinned? Why would God punish one person for sinning with death but the other with eternal conscious torment? If God's ways are equal, then shouldn't the punishments be similar? If "death" means "eternal conscious torment" where the devil is concerned, how can you be sure that it doesn't also mean "eternal conscious torment" for everyone else?
What I'm trying to point out is that regardless of weight of evidence of one side, even one contradiction would disprove your case. If the devil hath immortality and will not be destroyed by fire, and if he is cast into fire and tormented for ever, then he is not consumed by that fire and "Eternal Conscious Torment" is not only proved, but possibly implied for other fallen angels and even the race of Adam as well.
Are there other passages on the judgment that might be relevant here that we could use for context? I am not willing to accept a "biblical contradiction" explanation so easily. Are we misreading this somehow?
Yes. All of that neatly illustrates the problems with taking a passage from the Apocalypse of John and trying to insist that it must be taken literally. If a doctrine can't be proven using 65 Books of the Bible, then an appeal to the Apocalypse isn't going to help that doctrine. You must recognize the genre of the book you are reading in order to understand the meaning the author intended. When John explained what he meant by the lake of fire, he said the lake of fire is the second death. Speculation about what happens to the devil doesn't really help the doctrine of eternal torture. It reminds me of Deep Theological Discussions about the number of angels that can fit comfortably on the head of a pin.
Since there are many passages throughout the Bible that specifically state that the wicked will be destroyed, and that the devil will be destroyed, it is best to look at the verse from the Apocalypse as an anonomoly. It is okay to say "I don't know about that", but the overwhelming evidence from the Bible as a whole is that the wicked will be destroyed.