I loved this story! Others have mentioned the great atmospheric details and I also like, "He doesn't even suck once, and Sam's coming, coming so hard he bashes his wrist against the sofa's arm," it feels so natural, not to mention age-appropriate. It's a little silly to read these marathon sex sessions when the boys are so young.
I, too, would like to read more about that magna-creepy Buck, perhaps where Dean has to physically save Sam (or vice-versa) without any serious harm done?