First of let me say as a Dungeon Master the internet is a wonderful source of inspiration and general sillyness. One particular piece of amusement I encounter was the concept of the Meowl which was a series of pictures of owls with cat heads and vice versa, with the Owl Bear been one of my favourite fantasy creatures I was instantly attracted to the idea and my mind whirred with possibilities of how these creatures could inhabit the setting I'm working on The Free lands of Silverstein.

After a bit of trial and error I've finished the draft of the smallest of Meowls; the Lesser Meowl these small Meowls were the first to be created and generally used as familiars or pets amongst the wizard community.  

SPECIAL ABILITIES

Superior Low-Light Vision (Ex)

Initially bred as an minor project by an ambitious group of young wizards who wished to investigate why many man made magical species suffer from extreme aggression or insanity. The group was wise enough to start small having learned from the various recorded instances of creations turning on their creators and after several initial tests it seemed the combination of cat and owl would not only give them the comparison they desired but also additional chances of success due to a similarity in behaviours and prey preference.

Combining the speed and agility of the owl with the curiosity and intelligence of house-cats, the Meowl is a efficient hunter preferring to prowl nocturnally though if required can adapt to be active during the day also.

While they have avoid the insanity of similar creatures such as Owl Bears they have a tendency to be capricious as a species with personality varying between breed and individuals alike. Their somewhat moody temperaments has often had comparisons made to that of Griffins and some scholars are now beginning to believe that the process that created Meowls could of occurred on a larger natural scale in the development of Griffins.

They also have a intense predator instinct with a need to hunt which if they are not given a distraction or alternative outlet they will fall back upon which can be devastating on local rodent and bird populations (or anything tiny size and below really, Meowls will try anything at least once).
Meowls often crave a varied diet and occasionally horde food in times of plenty which results in them killing more than they can eat and false accusations of hunting for sport, they also will gift kills to another they see as close to them or they wish to mate with.

After startling success Meowls became popular as familiars and pets for those magically inclined much like falcons and hawks amongst the nobility While excellent (if somewhat narcissistic or sarcastic) familiars complications of keeping these animals as pets includes the combination of fur-and-small-animal-skeletons frequently regurgitated in place of hairballs, general difficulty in training and obedience and the fact that a larger Meowl breed if pushed can significantly injure a human.
It was no wonder that some Meowls either escaped or were abandoned retreating into the surrounding cities and countrysides where they adapted and flourished, after it was discovered they could breed true with other Meowls and both regular owls and cats (Resulting in a child of the mothers species).

The effect they have had on the landscape is telling and feral Meowls are considered a major problem in some areas, occasionally they will form packs known as Intrigues which will raid farmsteads for food often killing poultry and water fowl. One particular infamous group almost caused the collapse of a treaty with a fey court after slaying 30 of its smaller members and the truce was only held after a group of adventurers hunted down and slew the band including a Meowl that had achieved a mutation similar to a dire animal.

The Meowl mates frequently and enthusiastically though thankfully in small litters of no more than 4, pairing seasonally. Competition for natural resources and groups ranging from various tiny fey and druids to pelt hunters organising hunts against them has caused their numbers to fluctuate in recent decades but overall they are here to stay.