Can you explain how does action devil pet work?

When I was doing research on regarding which pet is the best I came across this pet and found some explanation on MapleSEA

Q regarding their chart:
1)Demon Pet is pre-evolved, and Devil Pet is post-evolved?

2)If above question is so, then is it confirm to get "Awakening Level 30
Only" buff effect? Or they just random buff like Roo pet's?

3)Do their WA buff stack whatever colors you get? I heard they are stackable in GMS but MapleSEA's mentioned

Spoiler

The Basic Buffs ‘Demon Pet Boost’ and ‘Devil Pet Boost’ can stack with each other, however you cannot have more than one of each basic buffs on at any point of time.

4)What does "Pet Fullness is between 100-125" and "Chloe's Enhance Potion" mean? Normal pet food doesn't work?

5)Does the "transform" command work on all bosses or it must "within 11 levels below and 21 levels above you"