Who Sent the Challenge?

Expanding a cute prompt: So, I've had a crush on a handsome guy in my class for ages. He practices sanda, but he's a big dummy. No matter how much I hint, he never notices that I'm in love with him~ Finally, encouraged by all my enthusiastic roommates, I summoned the greatest courage of my life and slipped a note into his textbook. It read: "On the night of * month *, at * o'clock, under the third tree from the left on the school's main sports field. Don't be late." I'm naturally shy, so I didn't sign it~?~? So he came, with what looked like a whole crowd of dark figures trailing several paces behind him. The moon was bright that night. When he saw the figure beneath the tree, he shouted, "Who dares challenge me?!" ...? The people behind him were a bunch of his buddies there to boost his confidence~~ After expansion, it turned into a historical fantasy... Premise: