My favorite and most beloved pet, Lady Proelium, is 'Very Happy.' Is this the maximum happiness, or can it be higher, such as a happiness stat like 'Overjoyed' or 'Super Happy?' Curious.

yes, thats the max. however, you need to buy an overlay in the Art MArket forum, asking for one here isn't allowed.

Are you some sort of Subeta Guru? Thanks, you're very helpful :D