Kyle Chutsky is a character in the Dexter Novels.
Featured as Deborah Morgan's boyfriend, he is a 40-ish former Black Ops assassin, who was retired from clandestine service due to injuries suffered on the job.
"Kyle Chutsky" is probably not his real name.
Kyle is a large, highly muscular man, whose presence intimidates Captain Matthews. He is covered in scars from his time in clandestine ops, including one across his right eyebrow and another down the side of his chin. When he first appears, he is wearing a nice suit, no tie, with the top three buttons of his shirt undone. On his left hand, he wears a diamond pinkie ring. His bright blue eyes are empty, and his wavy hair is artfully messed
Deborah is smitten the first time she meets him.
Kyle is portrayed as charming, though somewhat cocky, prior to losing parts of his limbs at the hands of Dr. Danco. He is flamboyant, exaggerating his emotional responses to cover the icy coldness held underneath, from all his time as a black ops stone cold killer. After his dismemberment, he feels he isn't good enough for Debbie, as he is "old" and ineffective. His insecurity finally leads him to leave Debbie for her own good, as he's failed to protect her one last time.
He was first recruited into black ops, when he transferred to "The Dark Side" of Special Operations in El Salvador in the 1990s. There he formed a political kill team with several others, including Dr. Danco and Albert Doakes, as detailed in Dearly Devoted Dexter.
Dr. Danco mutilates a former comrade, and Doakes recognizes the handiwork. Washington sends down Chutsky, who takes over the investigation. He and Debbie become a couple while working the case. When he's kidnapped by Dr. Danco, his little finger, complete with pinky ring, is cut off and sent to Debbie. Doakes, Debbie, and Dexter work together to try to get Kyle back. Dexter retrieves him from Dr. Danco's lair, short half a left arm and part of a right leg. Kyle finally screws up his courage to go after Dr. Danco, rescuing Dexter when Dexter fails to get Dr. Danco. He also rescues Doakes, who is now missing both hands and both feet, as well as his tongue.
Dexter describes Kyle as a cold killer with a "permanent attitude of knowing the real truth about everything." While he's at lunch with Kyle and Debs, Kyle has difficulty cutting his Cuban steak with his prosthetic left hand. When Debs brings up the case she's working on, Kyle offers to uses his "resources" to help, but she refuses.
Kyle has a special doctor fly in from Washington to help Debbie after she's stabbed. Then he assists Dexter in trying to kill the assailant by flying him to Havana and obtaining guns. Unfortunately, Brandon Weiss figures out that they are there, and they need to flee Cuba immediately.
Kyle is called in to back up Dexter and Debbie as they raid Buccaneerland and take out a The Coven of cannibals. Unfortunately, Debbie confiscates their cellphones because she wants the collar herself. As it passes, Debbie surrenders, Dexter is forced to surrender, and Kyle is taken by Brian Moser. Kyle sobs over Debbie's unconscious form but Brian soon rescues the trio. Kyle says to Dexter ("buddy" in his parlance) to tell Debbie that he loves her, and then drives off into the sunset. Debbie believes that Kyle thinks he failed to protect her and is just a useless cripple and should leave before he screws up her life anymore. This is just as Debbie becomes pregnant.
He has not had contact with anyone since, and may not be aware that he is a father.
Several different characters form different aspects of Chutsky in the TV series. Frank Lundy is the most obvious analogue, being also from Washington, D.C., sent for a serial crimes case, with a close relationship with Deb.