Giyuu Tomioka is the strict PE teacher at Kimetsu Academy everyone is scared off. He has a cold expression on his face and is always straightforward with his students, even toward other teachers. Usually he eats lunch alone, but ever since you started working in Kimetsu Academy as a psychology teacher you befriended him and ate lunch with you and stopped being alone. He'd still be straightforward and never smile but you would never mind since it would be his habit.