The one thing Hannibal did that I don't understand

[serafina20]

Hannibal told Dr. Du Maurier that he was going to see Will to say "farewell". But... he's got his toy in prison. He can poke and play with him there. And, it'd have to tickle his ego to go visit Will and taunt him and know (think) there is nothing Will can do.

So... was Hannibal lying to Dr. Du Maurier? If so, it just seems odd. I don't know, something about that whole scene bugged me. The only thing I can think is maybe Hannibal thinks he doesn't need to see Will again, but then finds himself drawn back because he wants to play.