I see these questions asked all the time, and while I'm working on making a complete Kawaii Pet Megu guide, I'll answer some of the basic questions:
How do I evolve my pet Megu?
You may have noticed the little lightening sign in the corner, and the curious little "plug" your pet has as a tail. Well, in order to get your Megu to change form and evolve, you need to play the game with your phone charger plugged in. You'll need to have done this 5 times until the lightening bolt is full, and then your megu will evolve.
How do I get a special evolution?
Leave your room filthy (don't sweep) and don't bath your Megu before charging it. Also, I heard repeatedly smacking your Megu right before charging it also works, basically neglecting your Megu. It'll lower your score, but you can always build it back up later.
My Megu won't tweet! Why?
Tweeting seems to be a mystery, but after playing the game for months I have noticed it only happens at night, after feeding my Megu and making it's satiety leap to almost full. If you link your Megu to your Twitter account, it just takes some time and patience. Megu don't tweet on a schedule, and you can't force your Megu to tweet; it's random and sometimes only happens once every two weeks. Try to feed your Megu something really good at night, that gives it a high satiety, thats how I got mine tweeting.
How do I level up my pet Megu?
Pretty simple, just feed your Megu yummy food, pet your Megu, and clean it when it gets dirty. You also get leveling points when you give gifts to other people. Giving the gift of an elixir or devo drug will even get you a 1000 leveling points without adding to your "satiety" bar.
What about Megu Score Points?
Your score on the Megu Leaderboard will gradually increase as you level up, but giving gifts, eating good food, and taking your pet for a walk every day will keep raising it. Moving into larger and better homes also increases your point capacity! Don't ever smack or pet your megu too much; it takes your score down a lot!
My Megu always seems unhappy, why?
This is usually the case in the lower levels, but you'll notice the higher you level up and raise your score, your Megu will start to have a better stress and "honor" titles. Just be patient and consistent. If you noticed your Megu has been ignoring you lately, well that's due to a glitch that hasn't been fixed yet.