A man spends the night at the woman he's been casually seeing, and wakes before dawn to a figure standing silently in the bedroom.

A wife and husband share a single reading account. One night she opens her tablet and finds a book in the library she never downloaded.

A woman flips through the Sunday paper over coffee and stops cold on a glossy wedding announcement featuring the man she has been dating for months.

A tip says her boyfriend is back on a dating app, but his phone is spotless every time she checks. She refuses to be talked out of what she knows.

A wife notices her husband's odd new habit of disappearing into the basement after dinner, always carrying nothing, always coming back lighter.

He swore he had never met her — until I scrolled up and found her number already saved in my own phone, under a name I did not recognise.