Anything wrinkled or disheveled is rumpled. Unless you make your bed neatly in the morning, your blankets will still be rumpled when you climb in at bedtime.
You'll make a better impression at a job interview if you wear crisp pants and an ironed shirt than if you show up in a rumpled suit. You can even describe a person as looking rumpled, if they seem generally messy and bedraggled. The adjective rumpled comes from the verb rumple, which is most likely a variation on the now-obsolete rimple, "to wrinkle."