I’m small and dark, yet ground for bite, often beside my friend in white.

I hold secret words and valuable letters, but I am only secured by trust. I can also hold junk, but I'm not a trash bin. Sometimes large, sometimes small, sometimes flat, sometimes... less flat. Take away my last letter and you'll discover what I do to my contents.

A vegetable, by any other pronunciation, is a saucy fruit.

When pyjamas rule and shoes retire, I help warm your feet beside the fire.

I'm always following a queen, A paradox, lose to win, Steal the end from any game, Now add a bit, that's the name.