This could be a hard question but I'm looking for non mainstream Japanese music. I'm a huge fan of underground emo, pop punk, rock, acoustic and hardcore. Anything is welcome. I'd love to listen to the non famous side of Japanese music. If anyone listens to any underground Japanese bands, please recommend me!
I just saw the Akabane Vulgars on Strong Bypass.. female punk-ish trio, really good. they just finished a US tour, all really small venues. picked up their newest cd at the show, it's really good

http://www.youtube.com/watch?v=XRl_Bw6Id3w

http://www.youtube.com/watch?v=YdU03o3TL28


also check out Uh Nellys. the guy has a really unique voice.

http://www.youtube.com/watch?v=EeS7xegsEgo
Oh this topic is interesting ^^
Do you found new groups finally?
Eek! I went inactive for a while but I'm back^^ I've recently been into Japanese shoegaze. Here are some of the bands that I enjoy listening to:

1. きのこ帝国 (Kinoko Teikoku what translates to Mushroom Empire) My favourite Japanese band. Their latest EP is amazing, I can never get enough of it. Keep an eye on them.. I know they're going to get big!

EP: Long Goodbye: https://www.youtube.com/watch?v=VKz5bw1m_i4
1st LP: Uzu ni Naru - https://www.youtube.com/watch?v=fkBIb_ElLRQ
2nd LP: eureka - https://www.youtube.com/watch?v=6wnfygDSgQE


2. She Her Her Hers. I can only find one of their albums on Youtube but nevertheless, it's a great listen. Their first album is on Spotify^^

Stereochrome - https://www.youtube.com/watch?v=rtHdXH7JEoU


3. Plastic Girl in Closet. Simple, cute and upbeat!

Cocoro - https://www.youtube.com/watch?v=u9RG5U_gIVQ


4. Mass Of The Fermenting Dregs. 

World Is Yours - https://www.youtube.com/watch?v=G4CKmzBf5Cs
Self Titled - https://www.youtube.com/watch?v=t01VmIMipKU (Skabetty is one of my favourites on this) 



Tell me what you guys think! Open for recommendations on Japanese and Korean bands^^ 
I listened to some of the artists mentioned here and I'm getting addicted to them. I like She Her Her Hers; just the type of music I love! I'd like to contribute to this thread but I'm not sure if the bands I'm going to mention here are considered indie or non-mainstream. My only indicator is that it's hard for me to find other references of these bands. Huhuhuhu.

Sotaisei Riron - This group has a unique and amazing vocals.

Clammbon - I can't determine their genre but their songs' melodies are very catchy.

Oceanlane - Their songs are all English songs. Maybe I'm wrong about this I don't recall hearing a Japanese song from this band. However, they are now disbanded. >__< They had around 3-4 good albums before they parted ways.

School Food Punishment - I first heard them on Eden of the East's (anime) opening or ending theme.

I hope I was able to spread love through music. *wink*