Mumus (called mom by biggies, "mum" in UK, but mostly "mumu") are penguins who adopt Pookies. They are normally very nice but they can sometimes be mean. There are a few different catagories of mumus.
Nice mumus are the mumus you most often see. They are always very nice to pookies. When you are adopted by one, they will be very sweet to you. Nice mumus are always kind and loving, unlike meanie mumus, which is why most pookies want them. New mumus are often nice but can be meanies too.
Meanie Mumus are mumus who are really mean to you. They can be Pookie Haters secretly. When you are adopted by one, they will be very mean to you, force you to do chores or even abuse you! MELMs are a type of meanie mumus that work in society and just abuse you. They abuse pookies by putting them in the oven, throwing them, locking them up and even skilling (killing) them.
Rich mumus are rare mumus with a cool igloo who usually pick divas and anything above. They usually only like the rare pookies and pamper and spoil you if you are adopted by one. They show their pookies off like they are wittle trophies. They spoil their pookies so if they are under the AMP rank of Diva, they become a diva. A lot of rich mumus are rare.