The dangerous beginning

In the dark world of mafia empires, loyalty means everything. Kim Taehyung, the ruthless king of Seoul's underground, never feared anyone-except losing Lisa, the only girl who made his cold heart feel alive. But loving her comes with a deadly price: her dangerously protective brother, Min Yoongi, Taehyung's own best friend and one of the most feared mafia bosses.

Now Taehyung must prove that his love is stronger than blood, bullets, and betrayal before Yoongi turns their friendship into a war.
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Taehyung doesn't beg. Instead, he proves loyalty through action.

One night, enemies attack Lalisa.

Taehyung risks his own life to protect her and takes a bullet for her.

After seeing this, Yoongi realizes:

"He is not just obsessed with my sister. He is ready to die for her."

Then Taehyung says something intense like:

"I'm not asking for your permission as a mafia boss, Yoongi hyung. I'm asking as your best friend. Trust me with one person more precious than my own life."