Conversation Between MuZ0NaZ and atal15

I'm looking for the name of a anime serie. There plot goes something like this:

A guy falls into a girl house while she was taking a bath. The girl promised herself that the one she will marry have seen her body ( im not sure if it was like this that scene). Then the girl starts to chase this boy. There is another strong women which can transform into a tiny child to a big women with black hair. After a few fights this girl trains this boy "something with the wind style". But the boy has incredable powers like a demon when he black outs.

The main character has blond-hair- black outfit.

Hello. Anyone here?