It is a website explaining Baru's name and showing the written consent she received from Valshe with regards to their names. Basically, when "Baru" started out in utattemita, she didn't know that Valshe's nickname was Baru so she received a lot of criticism. She was worried about causing trouble to the people and Valshe, so she asked Valshe for advice and explained that she didn't mean to "copy" the name (her "baru" came from "ganbaru" when she first submitted her work).

Valshe replied quickly and told her not to change her name because she thinks that the thoughts and sentiments with deciding a name shouldn't be set aside just because of a misunderstanding. She said that since she officially releases her songs as VALSHE and uses only Baru as her nickname, there shouldn't be any problem. At the same time, she apologized for causing Baru trouble because of her fans judging Baru just because of her name. She also said she wanted Baru to be recognized because of her voice and not because of her name, because her singing voice is really good.

I didn't read the whole e-mail in detail but basically, that's what it is ^^. Baru just put up the site to make sure people won't misunderstand and to tell Valshe's fans that they have reached an agreement with regards to their names. :)