The 10th game I played became the one I've played the most in my life: 'Fire Emblem: Three Houses'

I bought a Switch just to play Fire Emblem: Three Houses and started playing from the release date. Since I hadn't watched any of the official introduction PVs at all, I was surprised that it was about school life, or rather, that I would be playing as the teacher. Individually, Ingrid of the Blue Lions appealed to me the most, but if I had to choose a house, it would be Golden Deer. There are many characters good with bows, and I was also drawn to Hilda and Lysithea. During the mock battle, when I tried to attack the Blue Lions on the upper right of the map, a dialogue event occurred, and I can't forgive the fact that the Black Eagles and Blue Lions became aggressive AI. It's too much of a first-time killer. Also, you guys were fighting together, lol. What kind of mock battle is this? I reset and decided to attack the Black Eagles on the upper left of the map this time. And then I cleared it normally... I don't feel satisfied... After various things happened, for the July mission, a clearly dangerous enemy appeared in the center of the map. Their stats were as dangerous as their appearance. Strategic abilities are also hard to land... Huh? Come to think of it, didn't Lysithea learn a new spell? Death Knight: "＼(^o^)／" Time passed, and 'Ma!' went missing, so I went to search for them. And this month, I succeeded in my first recruitment. Ingrid and Felix became allies. And then, as soon as I proceeded with the Flayn search event, September ended. Why!?