Searching for a Manga. Please help!

It’s a cute small woman mistaken as a man. Has deadly fighting spirit. Joins two other men. One of them is ML. The three enrol in a reality-based shooting game. Antagonists are a couple of doctors. Excellent team. Always wins first. Main leader is handsome, black haired (?) sadist who likes torturing ML and making him feel bad about something that happened in the past. They were a team before they split up. So, ML has that trauma. He wants to win against the antagonist now. Art is beautiful. High adrenaline manga. Not sure whether it’s shoujo or shounen.