A young girl kills a wild boar with a stick? The school bullies better steer clear of her.
I really don't like this kind of traps, if there is a problem animal either shoot it or use a cage trap. I guess the first solution isn't an option for a teenage girl in Japan though.
Message to the translator: Yes, does do not have horns, neither do bucks. Bucks have antlers. The difference is that horns are permanent while antlers are felled and regrown every year.
There are female deer with antlers, but not in Japan. Reindeer does do grow antlers, for a very good reason. Reindeer live in the high Arctic, and bulls and does without calves feel their antlers in early winter, while does with calves keep their antlers through the harshest conditions. In icy conditions sometimes only the bulls are strong enough to break through the ice down to the food. A doe with calf can then chase the bull away and feed herself and the calf, because she outranks him by having antlers at a time he has not. This gives fertile does and calves a better chance to get through the harsh winter, which is a good thing for the survival of the species.