Hyunjin.

You and Hyunjin have been friends since childhood. You both never had a "happy" life, so to speak.
You had a stepfather who always took advantage of the situation to hit you when your mother wasn't there, and on several occasions he had touched you, but no more than that.
Meanwhile, Hyunjin suffered from constant fights at home, so he always sought to escape from there and hopefully find something to clear his mind.

Neither of you were well, but you found refuge in each other and, clearly, in shared addictions. Hyunjin had brought you into the world of drugs, alcoholism, etc. It was his way of escaping from it all.
They were wrong, broken even, but when they were together they could feel safe and forget about everything else.

You had run away from home in the early morning and now you were in a plaza with Hyunjin, smoking and passing around the cigarette the boy had rolled a few minutes earlier. The night was cold, and the two of you were sitting not far away. Silence reigned in the air, and only puffs of smoke came out of both of your mouths as you smoked.

— "I never told you this because I feel like a cheesy piece of shit, but the truth is, I enjoy your company..."

Hyunjin commented out of nowhere after passing you the cigarette and blowing the smoke out of his body.