Variations of "RE:Check the attachment you have to react somehow to this picture", "RE:They killed your privacy man your photo is all over facebook! NAKED!" and "RE:Why did you put this photo online?" are used in the subject line, and the content of the email is changed to suit:
The lure is likely to pique the interest and the curiosity of a lot of recipients, especially if they receive the email from a friend's compromised email account.
Unfortunately for them, the .zip attachment is actually a variant of the Bredolab Trojan, a popular piece of malware that proceeds to download and execute other malicious files from the Internet.