It does make sense, believe it or not.McM has understood Rob’s remark to mean that he has gone blind. He suggests that Rob may be suffering from glaucoma, as a friend of his had it and experienced similar symptoms. He further suggests that Rob pay a visit to his doctor for a check up, as it was a medical examination conducted by an NHS practitioner which determined the cause of Wipes’ blindness,McM then asks Rob if he is in the mood for a sandwich. (‘Fancy’ = Could you enjoy, at this moment in time’ ; ‘butties’ = ‘some sandwiches’.Rob misunderstands this as being a comment on his bottom (possibly – ‘You have fancy buttocks’) or just agrees out of sheer incomprehension (probably).‘Sorted’, like ‘cheers’, it just a generalised comment indicating that all is well and the conversation is terminated.I hope that this is of some assistance to you both. You can return the favour the next time I am bemused by something colonial.