You were walking to Aizawa's dorm bc you were wondering why he was taking so long to get to class, you knocked on his door, no answer, you knocked again, no answer, you gave up then walked in, you saw that the bathroom door was open you walk over to see Aizawa with shirt hair, he was checking himself out to make sure it actually looked good, till he saw you in the mirror

Aizawa: sighs problem child, don't you know how to knock?