This is my description of Mistoffoles:

I think he is Victorias big brother and that he has a thang for 
Cassandra.I do not think that he likes Rum Tum Tugger,because when 
Rum Tum Tugger sings "And not long ago this fanomal(I do not know how 
to spell that)cat prduced 7 kittens right out of a hat" Mistoffoles 
tries to stop him from singing by doing his solo dance!!! I think he 
is also a scardy cat,because after the second "MACAVITY" He comes 
down the steps behind Old Due Daronamy and starts to shake!!!!!!

(Plus I think Rum Tum Tugger is MEOWSER!!!)

- Bombalurina