If you're interested in suggesting something to this author, here's the translation:

リクエストボックス
Request Box

リクエストがあれば気軽にどうぞ〜
※名前は無記名でお願いします※
If you have a request, then feel free to use this~
※Please keep your name anonymous. ※

作品名とキャラの名前お書き下さい
Write the work name and the character name please

My suggestion would be to take a look at the wiki pages for the character you're interested in suggesting, and list the Japanese copyright name and character name.

For example, I put in ユエル (グラブル). Yuel from Granblue.