I found a thread from 4chan under /c/, here's what 2 anonymous users had to say about chubby girls in a chubby anime girl thread.
I've heard chubby girls make some of the best waifus, because:
1. They often know how to cook
2. They tend to be sweet
3. They are better for snuggling, and
4. More cushion for the pushin'
Lesser-known perks:
1. Fat keeps the skin elastic, resulting in fewer wrinkles
2. Many of them won't expect the attention, so they tend to be more enthusiastic about sex
3. Chubby cheeks are the cutest, have you even seen them
[spoiler]Kill me, later[/spoiler]
-
She can't have flabby elbows, more than one chin, and she can't look like she walks on her ankles or her feet are going to burst out the side of her shoes.