May

Tw: Transphobia and drugs mentioned in this one, but the Present section does not have any TWs

Martyr's younger sister (he has forgotten her and the rest of their family entirely). She fell in love with Lune, who came out as a trans woman when they were in high school, but was forced back into the closet by her parents making her cut her hair. She was also dependent on weed, and got sent to a rehab that also quietly practiced conversion therapy. Lune managed to escape, and came to live with May and Martyr. They were happy for a year or two, until the monsters began to show up.
Martyr panicked when they first arrived, and tried to burn them with a molotov because he didn't have anything else and didn't know what to do. Well, it worked. Their whole home caught alight, and it trapped Lune and May in the fire. May managed to escape after being scarred badly, but Lune died in the fire. May blames Martyr and Lune's parents for her death. If they hadn't sent her away, she never would have been in their home and never would have died. She killed Lune's parents, and came back to kill Martyr... but he was gone. She needed him to Feel the pain that she did. Every day, she wishes that he had died in the fire instead of Lune.