A portmanteau of "threating" and "romantic" from an episode of "Fairly Odd Parents" wherein Timmy Turner's parents try to help Timmy write an effective love-email to his crush Trixie Tang by combining the usual lovey-dovey cliches with threatening that she'd better date him if she ever wants to see her parents again.
It's threatening and romantic! It's threatmantic!
Threating and Romantic
"Someone stole my threatmantic email!"