Snape

There were clumps of tar and something even more disgusting and sticky under his fingers. The black substance coated Severus's hair, and if you looked at him from a distance, you'd think he'd put on too much gel or a strange hat.

Obviously, while he was sleeping, marauders had sneaked into the Slytherin dormitory and played another trick on him. Not a single strand of hair escaped the glue. He tried not to look up so as not to see his reflection in the row of mirrors on the wall opposite him. No cleaning spell managed to remove the mixture that stuck to his scalp like a thick shell. So no, he didn't go to class today. Instead, wearing only trousers, no shirt to hide his pale, sunken chest, and a terrycloth towel draped over his shoulders, gritting his teeth tightly, he stomped barefoot on the cold tiles of the boys' dormitory bathroom, sticking his head under the tap again and again, while Lily tried to soften the tar with shampoo. It softened, but he wasn't far behind, and his fingers dug into the sticky mess.

After a long half hour, Lily managed to separate the black lump into strands, but when Lily took her hands off his head, they were all black, with strands of hair stuck to them.

"Screw it! Give me the scissors," he said desperately, exhausted from the procedure, his back aching from the awkward position.

But he didn't want to go bald either. One could only imagine the rush of amusement this would cause, and the thought of it made him more nauseous than the acrid smell. Under Severus's guidance, Lily prepared a reagent to dissolve the resin without damaging his hair. They experimented with different solutions on several snipped strands of what had once been his hair. Steam rose from the water, and by now his cheeks, flecked with black spots, were reddened like the belly of a boiled crayfish. Millimeter by millimeter, he peeled away the sticky mass, shedding it along with a clump of hair.