Scribble creature

When Chloe Webber swallowed an Isolus, her drawings began to come to life. The Scribble was literally a living scribble of graphite animated with ionic energy.

When she scribbled out a drawing, the Scribble came to life. It hid in a garage. When Rose Tyler opened it, it leapt out at her. The Doctor shone his sonic screwdriver on the creature causing it to die and retract into a small ball.

While examining it in the TARDIS, the Doctor discovered it was made from graphite, which he demonstrated to Rose by erasing part of it with a pencil eraser. The Doctor and Rose then knew that drawings were mysteriously coming to life. (DW: Fear Her)