Sesshomaru's Fluffy
There is much speculation on what this so called fluffy really is. It is supposed to be Sesshomaru's tail, his boa, or his thing that appears around his neck while in his demon form (how cute). In all these arguments one thing remains the same. The fluffy is fluffy without a doubt and should be treated as an object of great value for fan girls to fan girl over. Many cases of this have been reported. Sesshomaru's fluffy is white (unless dyed pink by being washed with red as seen as a piece of fan art), fluffy obviously and very long. It is usually seen draped around Sesshomaru's shoulders. There are very few incidences where this is not the case.
The fluffy is the object of adoration by many many people due to it's fluffiness and prettiness. It is like a siren call to the weak and to the strong it is something to drool over from afar. Many possessive fights are held over who the fluffy actually belongs to although it should be very obvious that it belongs to me, ahem, Sesshomaru.
The theory that it is the tail of Lord Sesshomaru is the theory I support due to the fact he is never seen without it. It is also the same colour as his demon form and Sesshomaru's demon form is very fluffy. The fluffy is a tail for all of these reasons. Never once in the anime have I seen the fluffy actually separate from Sesshomaru's body. Nor have I ever seen it joined so I suppose I must acknowledge the other two theories.
The second theory that it is the thing that is around his neck makes no sense as the thing isn't really around Sesshomaru's neck. It is draped as a shawl around his shoulders or slung over his left arm. Thus, this cannot be the case. Which puts the tail theory in the lead.
The theory that Sesshomaru's fluffy is a boa is not unfounded. It is very fluffy, like a boa, it is slung around one like a shawl or over one shoulder much like a boa. With the appearance of and feel, by the looks of it anyway, it is quite possible that the fluffy is in fact a boa. This argument is disregarded by myself though because the fluffy would be much more appealing if actually a part of Sesshomaru. So, by a poll that I am the only participant in, the fluffy is Sesshomaru's tail.