The story is quite good! I love me some Cas/Dean and Sam/Dean. I did want to point out that the demon that tainted Sam in the crib was Azazel, the upper-level demon/Fallen Angel...not Ezeliel.

YAY! BE WITH HIM! Great story.

Possesive!Castiel, that is the best kind! I wish there was more stories out there with Castiel/Dean.

SQUE! That was great! xD

I think Dean was a bit too accepting... Like, he accepted the situation a little too quickly, ya know? Just sayin'. I still liked it though~! xD

Good job! d-(^__~)z

Other:
-the "fcuked up" in "(for whatever fcuked up reason)" seemed a bit much because this was not in a first person POV
-when referring to the seals, don't you agree that using the numbers instead of the words conveys a stronger feeling to it?
66 seals or sixty-six seals?
-"The interior was dark... upstairs." that sentence seems like it got away from you... :)
-you did this once before, but saying the same phrase more than once within a paragraph tends to sound awkward if it is not meant to hint at some literary element. ie "(when he knew all too well they could sometimes blend in almost too well)" see?
-""It's because...we are bonded."" Castiel doesn't seem like the type to use conjunctions at all, so "It's" should probably be "It is".
-"And suddenly Dean understood..." That sentence, it conflicts with what POV you are using. I'm not sure how to fix it though, sorry about that.
-You switched between "Cass" and "Cas" spellings.

Oh yes! Possessive!Castiel is so cute! xD xD xD

Very very~

Amazing altogether! (I don't think I get the eyes thing D: )

Next chapter! d-(^__~)z

I agree! This is coming out VERY well! "fcuking nasty" made me laugh... I'm not entirely sure why though... xD

Next chapter! d-(^__~)z

RAWR- AMAZING! I'm moving on to the next chapter! xD

PLEASE this was so good! please write some more!

Aw, horray! That was pretty good, and it piqued my interest. You're a very good writer. :P

Oh my, now that was delicious. I really like the Angel conversations at the beginning of the chapters, I'm guessing this is how it was for Anna before she changed back.

Yay, Castiel/Dean. I love possessive!Castiel, and the eye colour change (it seemed temporary for Castiel, not so much for Dean), one can only imagine what will happen when (not IF) they have sex.

Interesting to see the hints of Sam/Dean. I wonder how Sam will react to Castiel/Dean. Now that Ruby's been hit with the clue-by-four, I doubt she'll keep her suspicions a secret.

Ew, I hate Ruby.