Lady_Why?, are you still checking this thread for ideas? I know it's been a couple of days and your last post seemed rather finalized, but you also seemed to leave the gate open for more suggestions.
To be honest on the one hand I'm very glad that you've been open to new ideas and that you would go so far as to make a thread like this, but on the other hand I've been kind of disappointed in the ideas people have been giving you. It seems like everybody's trying to get their favorite guro scene in your story, and while I suppose I can't blame them for that it might not work out the best for you.
You've only given us a little bit of information concerning what your story is about, like in
>>1 when you talked a little about your main character that seemed supernatural in origin. It seems like people might have missed what you said, though, so I can talk a little about the abilities you said your character had.
First, blood manipulation has a lot of different possibilities. I'm very glad you decided on something like this, because I think it's very poetic. Have you come up with ways you plan on using this yourself? It might be easier to talk about expanding on something you already thought of rather than try and cram new ideas into the story. But anyways:
Blood Manipulation Ideas:
- Exsanguination (Bleeding to Death): There are different ways you can go about doing this as well. This is a versatile form of death because you can either make it quick or drag it out for some time as well. Depending on size the average human body contains between 10-12 pints of blood, which is about a little over one gallon to one and a half gallons. A quicker death could involve all that blood bursting out of the body at once. Depending on how sexual you wanted it to be you could choose those particular orifices, but otherwise you could have victims vomiting up all their blood or etc. You don't even need to use a natural escape, you can have the blood rupture through a chest cavity or the like as well.
Approaching it from a different angle, bleeding to death the slow way works more like real life. You could either make this part of a normal death-someone with an injury or missing limbs bleeding to death naturally, or have it be part of the supernatural aspect as well. The example I'm thinking of as I type this is making someone with no physical injury bleed to death through the pores of their skin, under their finger and toe nails, out their ears, etc. This would let you kill a character of gradually and sustain greater damage along the way (they could lose their vision when they start bleeding from the eyes, for instance). I myself am fond of the idea of making a character in this situation panic and try everything they can to make it stop, only for all their efforts to be futile (if you did take it slow and they were only bleeding from their fingernails at first they might be forced to cut their hands off, only to have it get worse from there, etc).
- Internal Hemorrhaging/Damage: Blood is everywhere in the human body so manipulating it means you can damage any part of a victim. Organs all need blood to function, so you can destroy someone's stomach by causing it to burst, deprive someone's brain of blood (which would likely cause a lot of insane psychological damage before death), or even fill their lungs and make them drown in their own blood. Blood is mostly water and water can be one of the most destructive forces on the planet. Assuming supernatural control of blood pressure you could even make it crush someone's bones or act like a high pressure cutting tool.
I think my favorite scenario for this type would be manipulating the blood flow causing a victim's heart to beat faster and harder until it explodes.
- Blood Outside the Body: If you do have a victim pop like a water balloon do to blood pressure or just tear them apart in any number of other ways it's going to be a very messy affair. Although I think it might be less appealing to use blood outside the body, there are still some possibilities here. Just for general slaughter like I said before blood function practically the same as water and can crush, slice, rupture, etc. Depending one how supernatural the blood manipulation is you could form blades of blood, bonds of blood, or going a more sexual route bloody tentacle rape and the like.
Favorite scenario here I think involves forcing more blood into a victims body, either going for so much so that they explode or making the new blood tainted/destructive to the body.
- Transmutation: And I think that last point leads into this one, if this is supernatural manipulation of blood it could be changed into something else. One of the ideas you were already given was being injected with acid, and this would work on the same principle. You could do the same thing with any number of ideas-fire, poison, molten lead, etc.
Moving on from that the other thing you mentioned was commanding helldogs. This one I do really like for personal reasons but it's harder to comment on because I'm not sure exactly what you mean when you say Helldog. I am going to assume they're canines which beans they are capable of biting and tearing someone to death. Depending on their size you have the option of both soft and hard vore. If they breath or piss fire or have any kind of supernatural attributes you have that option available as well. For a more sexual turn I'm sure I've already seen stories here where people are gang-raped to death by dogs.
I'm really interested in seeing your story and if you get this message it would be neat to hear more about the character and the situation you intend to present. I don't know if you plan on being brutally realistic or with the more supernatural elements be more fantastic. I do think that something you should consider, whether you killer can keep people alive for torture or showing them their own organs or since you mention horror movies just having a bloody killing spree in the style of Jason Vorhees or his contemporaries.
Whatever you decide to do, I hope we get to see the story.