I use Gmail to collect my email from my work server. Hey, Google has more storage space than God; why not? But I have recently discovered that the Gmail spam filter does not like the word adult. As in young adult novel.
Oooops. Who knew Google was such a prude?
I just found about fifty or so queries tucked away nicely in my spam folder, all of them with the word adult in the subject line.
So just a word of caution: try not to put the word adult in the subject line of your query to me. Gmail might inadvertently eat your email.