Cosplayer Ellen Hardy went big and cuddly when she decided to cosplay as Baymax from Big Hero 6. The above picture may look like a massive plush, but no, there’s a person in there. She said she has hand held fans and water inside the costume — there’s lots of space in the torso — so she stays cool enough, but boy, it looks warm. Many of Ellen’s other costumes (you can see them at Facebook) involve armor, so Baymax especially stands out. She hasn’t posted any notes about construction of the costume, but I’m guessing she used something like upholstery foam to make the costume both comfortable and huggable.
You can see the pieces of the costume below, but if you need any further proof that it is a costume instead of a plush, you can see Ellen in the costume hugging a cosplayer dressed as Groot at Instagram.