wallywashis.nameは安全ですか？

It's just a hoax. The music index is a copy of the MusicBrainz database. Some of the artists the site claims to have when searching (such as, oh, MusicBrainz Test Artist) don't have recorded material that exists in the .mp3 format. If you stumble upon one of those directories, refresh the page. The file sizes will change. Seriously. There is absolutely no music on this site. On top of that, the site lures in unsuspecting visitors to waste their time by forcing them to finish potentially malicious surveys to "create" an account. However, no matter how many you finish, nothing will ever happen. The site's owner, on the other hand, gains revenue for every useless "free offer" that is completed. Stay far, far away from this site.

Don't waste your time: ad-spam, i.e., in order to use his site, you must complete a SPAMmed "free" offer/survey. "To help support downloads you must complete this free offer before your account will work. You will not be able to download until you complete the survey or free offer."