thats because the chapters 9-12 are missing here. What's here as ch. 12 is actually extras. Real ending is here, from 9-12.
http://www.mangatraders.com/manga/series/4122
The chaps 12.1 and 12.2 are the two extra chapters that sensei did after the last volume....to sum it up mangago is missing the last volume chaps 9-12 but has the actual ending which is 12.1 and 12.2 which mangatrader is missing.
Soo many questions?!?!?!?!?!?!??!?!?!?!??!
I don't understand why the father is his love, so confusing. The beginning was really cool and new, but the end just kills the whole story