Answer:
My teeth are sharp my back is straight to cut things up it is my fate.
I like to twirl my body but keep my head up high. After I go in everything becomes tight
In spring, I am gay in handsome array. In summer, more clothing I wear. When colder it grows, I fling off my clothes. In winter, quite naked appear. What am I?
You hold my tail while I fish for you. What am I?
Soft and cuddly I'll pull on your heart. But take my last name and I'll tear you apart.
It has no top or bottom, but it can hold flesh, bones, and blood all at the same time.