Guns and StampsTaihou to Stamp

The story is set in an alternate world with 20th century-like technology, during a great war between the alliance of the Grand Duchy (Russia that never formed) and the Empire (Poland-Lithuania that never fell into ruin) on one side, and the Republic (the Ottoman Empire that never fell apart) on the other. Lieutenant Martina M. Mayakovskaya is a new officer in the Grand Duchy Logistics Corps. It's a branch of the armed forces responsible for transportation and supply that is looked down upon by the rest of the military as "paper soldiers". Martina's assignment is supposed to be a comfortable desk job dealing with stamping paperwork, but for some reason wherever she goes, she ends up in the middle of combat. Also, what's that eight-legged pseudoweasel that she adopted as a pet (or it adopted her?), and is it just a coincidence that it seems to be saving her from harm every time?