What kind of online shopping is it? I mean who are u buying from..Is it individual sellers like ebay without the bidding or something like a online department store
It is a bunch of individual shops grouped together through one site. Some of the shops have very limited English, so it can be hard to work out what's going on.
It's worth looking at, because sometimes you can get some good prices on Japanese made clothes, or items only released to the Japanese market. I've bought from Rakuten before and had no problems. You won't get a computer virus, just a whole bunch of awesome semi-translated Japanese.