Clue: 'Latch heartless Doctor Faust', wrote von Goethe, bitter at the end (4,8)
Answer: DOOR FASTENER
Explanation: Definition: Latch
A charade of DOORFAST ('do[ct]or fa[u]st' minus their middle letters – 'heartless') plus E N E R ('wrot**E** vo**N** Goeth**E** bitte**R** at the end').