So, I've just played the game through all the provided endings (I won't spoil anything, though).
Great game, indeed! Very thoughtful. The T-Gotchi bristles with life, and it's rather easy to want her happy.
In my humble opinion, however, the game is way, way too short. There should have been more to explore in the relationship, more nuances to add and maybe a bunch of extra endings too.
I hope there will be soon a new or extended version. I'm looking after it!