Pink Finger a.k.a. 'Taggers Thumb' is a fictional condition caused by a rare cancer of the spine which causses your digits turn un-natural colours. In reality it is a result of too much stencil-bombing.
1. Ant: Mum, can I have the day off school, my pink finger's flared up again?
2. Tom: Ant, move you hand or you'll get pink finger.