Pikachu and Godzilla are only a barely-registered beginning to Japan's extraordinary list of native monsters. Bakemono, literally "transforming things," are a varied phylum of creatures dating back centuries in Japanese folklore. They are generally divided into three classes: oni, the horned, fanged demons and ogres who guard the gates of Buddhist hells; yurei, the vengeance-hungry spirits of the dead; and youkai, the "bewitching apparitions" who are sometimes scary, but more often just amusing and bizarre.
Youkai are by far the most fun group of monsters. Here are some of my favorite:
Ittan Momen is a three-meter long length of white cotton cloth. It enjoys flying around, and occasionally will alight and attach itself to random passers-by. When frightened or upset, Ittan Momen may suffocate and strangle people; when it is happy, it will sometimes let itself be worn.
Kappa is a green bird-like creature with a turtle shell and a concave-topped head. It is alternately malevolent or mischievous, and it might suck your innards out through your anus, or it might just blow up your skirt. The kappa is easily diverted, and many have escaped him by tossing him a cucumber, his favorite food (hence the cucumber sushi roll called kappa-maki). He can also be extremely polite and bound by tradition. If you meet him and can maintain the composure to bow, he must bow back, thus spilling the life-giving water he keeps in the depression atop his head, and forcing him to run off to refill, while you make your escape. If I have any survival advice for those going to Japan, it would be this: always bow to kappas.
The kasa obake is one of the class of tsukumogami obake, everyday objects which gain life through long-term use. Some believe that objects come to life upon their 100th birthday, perhaps one reason why there are so few thrift stores in Japan. The kasa obake is an animated paper umbrella, with one huge eye and a large lolling tongue. It has a single leg instead of a handle, the foot clad in a wooden geta, which clacks as it hops around. Kasa obake aren't particularly dangerous, just disconcerting, and in fact they are quite playful, especially on rainy days. Another common type of tsukumogami is the chochin obake, a floating paper lantern, with a horrible ripped-paper grin.
Kera-kera Onna just wants to make you laugh. She has a comically overly-large head, loves making silly faces and wearing showy costumes, and wanders the land looking for people to cheer up.
Konaki-Jiji is a big baby. Or at least he looks like one, until you pick him up. He lies roadside and plays the abandoned infant, crying until someone picks him up. Once he is safely cradled, he rapidly grows immensely heavy. When his unsuspecting victim drops him, he immediately vanishes, leaving the person stunned. Those who are able to carry him despite his weight are sometimes rewarded with wishes.
Kuchisake-Onna's story is tragic. She was once a famously beautiful woman, until a jealous suitor hideously disfigured her face, carving a Joker-like smile ear-to-ear across her mouth. Now she wanders streets in a surgical mask, especially on foggy nights, asking passers-by whether they find her beautiful. Usually, the moment she removes her mask to ask the question, people will run away. She will chase the unfortunate victim, and carve their face to resemble hers. Sometimes an escape can be made by throwing her fruit to eat, which she loves.
Mujina look just like people, but they have no faces. They know exactly how creepy that looks, and they take delight in scaring the bejeezus out of humans by assuming the shape of familiar figures but for the one detail. You may think that's your waiter you're flagging down, or that traffic cop who's been trailing you for miles, but look again.
Nando-Baba lives in abandoned storage rooms. She's quite happy with that arrangement, and is peaceful unless disturbed. If she is bothered accidentally, she may try to scare you away. The lesson is to never, ever try to clean out your closets.
Nurikabe is a wall of invisibility, who gets its kicks causing people to get lost. He may wait at one end of a pathway, making you think you've gone as far as you can. Sometimes, he might even absorb you into him, although usually it's just temporary. Nurikabe may also provide an interesting excuse for why you were late to work.
By day, a rokurokubi seems to be an elegant, beautiful woman, tending toward self-indulgence and pleasure. By night, she is a life-sucking monster, seeking her usually male prey by extending her snake-like length. It does no good to ask a woman if this is her tendency, because often she herself does not even know.
Sunakake-Baba isn't such a bad old woman, she just likes to stand near roads and fling sand at people. She thinks it's funny.
Tansu-Baba is another quirky old woman, she lives in abandoned chests of drawers. It's a lonely life in there, and occasionally she will pull people in for a chat, letting them go when she's had her fill of their company. No one really knows what she chats about, as most people have only a very fuzzy recollection of the event upon their release.
For more bakemono, go here. For an interesting analysis and history of bakemono, go here.

