subplot 003.

[Rebecca Catalina]

Amestris

■ ■ ■ Hawkeye, Riza » current age: 27
■ ■ ■ ■ Mustang, Roy » current age: 31
■ ■ ■ Grumman, ------- » current age: 70

It is obvious to everyone that ■ ■ Riza Hawkeye and ■ ■ Roy Mustang are in love with each other... except, perhaps, the couple themselves.

Having studied alchemy under her father, ■ ■ Roy has known ■ ■ Riza since they were children; it was because of him and his dream that she joined the military; it is because of him that she's still there. She is his adjutant, and they are both, admittedly, dependent upon each other.

But I'm sure that everyone already knows that.
What most people don't know, however, is that the reason that ■ ■ Roy and ■ ■ Riza cannot get married is military regulations (fraternization laws) _{(source to be updated once I find a reliable one in English)}

...That's where the new Führer ■ ■ Grumman, ---- comes in. In addition to being Führer, ■ ■ Grumman is also ■ ■ Riza's maternal grandfather - and he wants Roy and Riza to get married. Primarily, it is to be assumed, so that his family still has some significant power once he (presumably) abdicates, but there is certainly suspicion that he has been trying to play matchmaker for the pair before ■ ■ Roy becoming führer seemed like a feasible option (and, as of right now, ■ ■ Roy is certainly ■ ■ Grumman's first pick for a successor)

To achieve this goal of successfully securing his granddaughter as the future first lady of Amestris, ■ ■ Grumman is certainly planning something. Right now, his options seem to be: 1. reassign ■ ■ Riza to a different commanding officer, thereby circumventing the fraternisation laws without actually revising the laws themselves, 2. revise the fraternisation law to include a clause that would allow ■ ■ Riza and ■ ■ Roy to get married, 3. abolish the fraterinisation laws completely, or, 4. declare an order that ■ ■ Roy and ■ ■ Riza get married (and find some way within that to circumvent the fraternisation laws).
Which will he choose?
We'll have to wait and see.