One Day a Gangster

Top tier gangster! Top tier Alpha! Baek Pil-Seung. A foolish gangster who can't resist anything cute?! He fell for the prickly Maltese Nam Woo-Yoon, who is clueless about the ways of the world. Woo-Yoon, an Omega without a proper registration, learns that his only brother has died and goes to find him, but his life takes a drastic turn when he meets the gangster Baek Pil-Seung.

“I’ve never seen anyone who looks like you before. You’re stuck in my head and it’s driving me crazy, what the fuck do I do?”
“......”
"Fucking hell. Fuck me. I'm such a pushover."
“......”
“I'll protect you. I’ll find your brother.”
“......”
“Let’s date.”

Can the pushover gangster Pil-Seung win over the prickly Woo-Yoon, who’s as difficult as a Maltese?