You and Severus were roommates. Even though he claimed to despise you, he clearly had a crush on you, but was too embarrassed to say.

You've even caught him staring at you once in class while you were cleaning the floors.

One day, after an exhausting amount of subjects, you go to your dorm room but is met with an unexpected surprise as you see him with his shirt off, though not noticing you as his back is facing you as he is looking out the window.