Lord Death's POV
(Y/N) and I were in the death room talking when I felt a strange soul wavelength. That's when the death room door opened and (Y/N)'s eyes widened. The soul wavelength I felt was approaching (Y/N) and me. It was a witch's soul wavelength that I felt. "Hello, (Y/N), how has my darling daughter been?" The witch spoke. "You're no mother to me, Arachne." (Y/N) told Arachne transforming into twin katanas. Arachne just laughed and said "You actually think your good enough for my daughter Reaper. I didn't come for trouble I just came for (Y/N)." "Well, you can't have her. Besides it's not your choice if she gets to be with me or not." I replied. "Fine if you don't want to give her to me peacefully I'll just take her from this place." Arachne said venom dripping from her voice. Since, I was using her as my weapon we could hear each other's thoughts. '(Y/N), if Arachne is your mother how are you a shadow witch?' I thought to my weapon. "(Y/N), transform into a scythe." I spoke as she transformed into a scythe. 'Arachne gave me to my aunt Medusa for her to use me as one of her experiments and somehow turned me into a shadow witch.' (Y/N) thought. That caught me off guard and I lost my concentration causing Arachne to get an upper hand. "Lord death!" I heard (Y/N) yell as she turned back into a human protecting me with her body. Her mother hit her with her strongest spell not knowing it was not me. When she realized who she hit she gasped and ran off without her daughter. My eyes widened as I saw blood start coming out of where Arachne hit (Y/N) with her spell, which was her chest and stomach, without a second thought I brought her to the nurses office. Carrying her in my arms her blood started to stain my white gloves but I didn't care all I cared about now was saving my beloved (Y/N).
Time skip to the nurses office
I heard the infirmary door open and I turned around to see lord death and in his arms was (Y/N), but she was unconscious and very, very pale from loss of blood. "Stein, please help her." The shinigami spoke worry and sadness filling his voice and I could also see tear stains on his mask. I nodded and took (Y/N) from him and placed her on a bed. I started preparing her for a surgery to close her wounds. I asked lord death to leave and he did.
Time skip to after the surgery
When I walked outside of the infirmary and saw Lord death look at me. I could tell he was worried even with his mask on. "She'll be fine. It should be a few days till she wakes up." I told him. When I said that he let out a sigh of relief. When he went to go see her I stopped him. "You need to stay next to your mirror lord death. I'll stay by her side as soon as she wakes up I'll tell you I promise." I told him all he did was nod and look at (Y/N). After a few minutes of silence he spoke "(Y/N), please stay with me."