how do I repel a oni or youkai ?

my friend keeps on seeing a japanese girl appear outside of his house and he's getting affraid of the girl . It's possible she could be a oni , youkai or ghost .

Ryukokun,

If she's an oni, try pelting her with dried beans. If that has no effect, I suppose you could try raw eggs or even bricks instead.
Whatever course of action you take, be sure to video it and upload it to YouTube.

A: Tell your friend to stop entering abandoned houses.

B: Based on what I have learned from movies (which are clearly never wrong) your friend is doomed no matter what you do. I'm sorry.

C: Try Dave's suggestion anyway. It sounds like he has experience in this matter. :P

Tell him not to bathe for a week. That'll repel anyone living or dead.

Is the ghost cute? I'm sure it would be an excellent experience for your friend to hook up with ghost-chick. If she hasn't tried to kill him yet, there's a good chance she wants something else ;)

Salt is used to purify a place. An annoying neighbor used to pour a tiny cone of salt on the edge of a friend's doorstep (to purify the house of my friend, who was a foreigner married to a Japanese man).

I'm sure there's other ways, but that's one I know of.

Salt would be my first choice. Line every window sill and door frame with it.

Secondly, cinnamon and/or rosemary work fairly well as "I mean you no harm, but please go away" type of non-offensive charms. So does Quartz, and any bits of silver (.925 is good) hung around windows or doors, especially if you see her in one place uniquely.

Have you/your friend tried communicating with her? I wouldn't jump the gun saying she's oni or youkai as they're generally malicious and destructive, or at least apt to steal and hide your car keys. Kitsune, maybe, but they're typically proactive in their annoyance towards people. My bets on a plain ol' ghost. I recommend having a medium try communicating with her, or else ask a local temple to formally purge and bless the dwelling.

If she hasn't done anything yet, chances are she's just confused/bored/lost and not malicious at all. (Most ghosts generally aren't.)

Have your friend go to a temple or church & get blessed by a priest.

Any addition info about your friend? Did he do something he wasn't supposed to do?

You want a relationship?

That should get rid of her...nooo just kidding

I was staying in a friends house in Japan and they had 2 different ghosts its funny cause i only see ''American ghost here i guess they cant cross water...Ive heard some of these ghost r hungry and u make an offering to them food money etc...i think its a good idea to have the property blessed...Good Luck