From the outside looking in it's a beautiful relationship, both loving and caring, maybe (Top) can be a little possessive however it wasn't too concerning for anyone and didn't seem to bother (Bottom)
Although, every relationship has its ups and downs, (Top)'s being his hobby of murdering. Of course he would never touch a hair on (Bottom)'s head, he adores every part of him. (Bottom) is aware of the situation, trying to get his lover to stop countless of times.
Eventually they came to an agreement, (Top) could only murder someone who had done something horrible, seeing it as karma almost.
Will (Top) keep his promise? Will (Bottom) grow tired and leave?