Baemui Simyeon

Jae-Hyeon, an ordinary college student, has been suffering from unpleasant dreams recently. A very unpleasant dream where a giant 'red snake' appears and stares at him or squeezes his body to the point where he can't breathe. The day after having the dream, he always gets a headache that feels like he's going to burst, but when he goes to the hospital, they tell him that there's nothing wrong with his body. Then one day, Jae-Hyeon, who was on his way to his studio apartment, collapses on the street and receives help from Soo-Yeon, a senior he's not close with. From that day on, Soo-Yeon actively approaches him, saying he wants to be close with him, but Jae-Hyeon can't bring himself to push him away...

(Source: Bomtoon, translated)