A wolf can eat as much as it can and go on hunting the next prey. The day it is too fat to catch the prey he will skip the lunch, and this keeps a wolf as fat as possible while being always fit enough to hunt.

If you take that wolf and give it unlimited food it will eat until it dies.

You are the same. Problems are:

1 your heart can’t pump blood to feed the gigantic muscles you need to move your fat around. Your heart will soon or later collapse for fatigue.

2 fat piles up in your blood too, and can clog your arteries. This can give enormous pain when a clogged artery stops feeding some tissue, and that tissue dies. But this can happen to organs too. It can happen to your brain or heart with fatal results.

3 kidney & liver are sized to keep your body clean, if you increase your body size too much they won’t keep up properly. Long term diseases will come.

4 you rot. Yea your tissue needs blood to live and if you are fat enough to not move enough, some parts will simply be compressed onto the sofa, receive too little blood, die and rot. Skin is one of the most likely early part that will die and rot.

5 you can’t run. There may be a fire or some other hazard and you can’t simply escape.

6 good news, fat floats better than bones so you won’t drawn easily at least. Also you can resist cold a bit longer.