Responses
Someone pointed out the ghost maid had two extra skulls on her back symbolizing she been carrying/feeling guilt for both touma's and hayato's death. I think we can safely guess that hayato died shortly after touma in a way that the maid blamed herself for (since she didnt deliver his letter in time).
I may be bad but I really want to know what happened to Hayato after Touma is gone
Did he regret it so much? But how? I want to see he's grieving ╥﹏╥