I think the mc was a woman from noble family or such that got decimated by the emperors order or such because they are too dangerous and framed as "rebel". the one who surviving was a teen girl age 15 who was the daughter of the noble family. she then start dressing as a man to hide herself and seems want to get revenge i remember there's a scene where she buy an expensive cold ice cream shaped like dumpling and feed it to the enemy soldier(it contains sleeping pills) and then managed to sneak inside the building. Much later, the dumpling ice cream store got burned down by the official thinking them as "rebel". The girl feeling guilty seems taking a boy who was an apprentice on that store(he was orphan and taken in by the store owner) the novel also have a web comic on , and it was released in around year 2015 i think(translated)