Board Thread:General Discussion/@comment-120.148.81.195-20140728101523/@comment-24994749-20140729043953

My main guess is that he made some stupid bet about arriving to Vale for free.

Then there is Ben's theory about the adrenaline addiction which seems to fit Sun's personality pretty well.

And Zolnir's sounds like something Sun would do, too.

Then there are the "Sun is a prince" ones but those are extremely unlikely.