Well Matsu was helping him try to keep him from changing for abit but he was showing signs of his change from quite early on.
I think Kagari's change accelerated more as Minato winged more Sekirei.
Like I've said before I'm just more interested in wanting to see Kagari par take in the shopping battle
the tought of Kagari feeding Minato just........ah I get all giddy thinking about it
.......ah time for a cold shower to cool my head