[kokolores]

Why would he be angry?

Spoiler:

It's not as if Yuri being adopted by another family would really change anything between them. I would think that he'll pretty much mirror Yuri's stance on the matter. Only if Yuri is against it, whether openly or hiding her true feelings out of a sense of duty, will Godou see any reason to intervene. This looks like the typical political maneuvering to me and Godou has no interest in such things, besides I doubt he has any real appreciation what being adopted by another family like that would entail.
I think far more telling to this development are Erica's and Hikari's reactions and perhaps Kaoru's as well. They are the ones who are politically savvy enough to understand and act on this and in Hikari's case she would be the one to tell Godou whether Yuri is forcing herself