Randy, I teared up just thinking of your upcoming separation from Kazumi and Muffin!

The weight gain is from boredom during your absence. Very typical. And the needier behavior. She felt abandoned on some level. Ben and I had a similar experience with our cat Tango when we left him for the first time. Most people think cats are aloof and self-contained, but that is simply not true for many cats. They really do miss us when we leave.