The phrase "a shadowy character" is correct and usable in written English.
It can be used to describe someone who is mysterious, secretive, or possibly involved in dubious activities.
Example: "The detective was on the trail of a shadowy character who seemed to be pulling the strings behind the scenes."
Alternatives: "a mysterious figure" or "an enigmatic person".
Since we never learn anything about Lears outside the classroom, he's ultimately a shadowy character; he's in the way of a deeper exploration of our protagonist, Edmundson himself.
When the Libertines' Pete Doherty first became embroiled in heroin and crack cocaine, internet messageboards mentioned a shadowy character called Wolfman.
If you had a nightly TV show with an audience of 5MM, is there a shadowy character that you would cover and attempt to expose?
Set to music by Moondog, it promises a "four-part investigation of the subversive nature of a shadowy character," with a new section each night.
I would often just put fun little things in as I went along – a shadowy character here, or a mysterious moment there – and I didn't necessarily know where it was leading.
We are privy to the dream vision of Humphrey Chimpden Earwicker in "Finnegans Wake," and we are privy to the hallucinations of a shadowy character named Gil in "Gilligan's Wake".
She has got herself invited to America by Harold, a rather shadowy character who is using her to get to Doctor Wheeler in order, we learn eventually, to take revenge on him.
Television Without Pity called Walternate's sudden appearance one of 2010's "Most Memorable TV Moments", explaining "We knew we'd meet him eventually, but the way they surprised us with him at the end of a stand-alone episode was a fitting introduction for such an ominous and shadowy character, and we knew even then that it marked a new and improved era for the show".
Which brings us to Lila, the latest Gilead novel, telling the story of John Ames's much younger wife, a pivotal but shadowy character until now.
He did not evaluate Mr. Hopkins's Hannibal, but said he thinks the killer works best not as the central character but as a shadowy supporting character, outwardly normal, with his madness obscured, only glinting darkly in one brief scene.
Rather than circulating a digital currency, the shadowy character of the piece's title, A. M. Monius, has written a metaphysical treatise, "Coming to Understanding," and has paid prominent philosophers twelve thousand dollars each to review it.
