comment but have attribute like placeholder (html)

[kito fool pace]

is there plugin that has function same as comment but it look transparent (text have gray color) like placeholder?

when user write, it will be rewrite text transparent, but, the difference placeholder and this, this text transparent will still there, not disappear like placeholder. . .

i just want create something like tutorial, so they can just write exactly same as that text transparent i create. . .

if there is one, please tell me which plugin should i use. . .
#even if you just read this, please let me say thanks